CATDOLL : CATDOLL: What types of organic fertilizers are there?

What are the types of organic fertilizers? Organic fertilizers in a broad sense:

Commonly known as farmyard manure, it is composed of various animal and plant residues or metabolites, such as human and animal feces, straw, animal residues, slaughterhouse waste, etc.

It also includes cake fertilizer (rapeseed cake, cottonseed cake, bean cake, sesame cake, castor cake, tea seed cake, etc.); compost; fermented manure; manure; biogas fertilizer; green manure, etc.

It mainly uses the supply of organic matter to improve the physical and chemical properties of the soil, promote plant growth and the circulation of the soil ecosystem.

Some types of "organic fertilizers in a broad sense":

1. Compost: A fertilizer made from various orange stalks, fallen leaves, grass, animal and plant residues, and human and animal feces, which are mixed in proportion or with a small amount of soil and then aerobically fermented and decomposed.

2. Fertilizer: The raw materials used for composting are basically the same as those for manure, but they are fermented under flooding conditions.

Manure: refers to the fertilizer made by composting the excrement and urine of livestock and poultry such as pigs, cattle, horses, sheep, chickens, ducks, etc. with straw bedding.

3. Biogas fertilizer: In a sealed biogas digester, the byproducts of the decomposition of organic matter to produce biogas include biogas liquid and residue.

4. Green manure: using cultivated or wild green plants as fertilizers, such as mung bean, broad bean, sweet clover, sesbania, alfalfa, and vetch from the Leguminosae family. Non-leguminous green manures include ryegrass, radish, sunflower, Azolla, water hyacinth, and water peanut.

5. Crop straw: Crop straw is one of the important fertilizer varieties. Crop straw contains essential nutrients for crops, such as N, P, K, Ca, S, etc.

Under suitable conditions, through the action of soil microorganisms, these elements are mineralized and returned to the soil to be absorbed and utilized by crops.

6. Pure natural mineral fertilizers, including potassium ore powder, phosphate ore powder, calcium chloride, natural potassium magnesium sulfate fertilizer and other natural substances that have not been chemically processed. Such products must be certified organic and produced in strict accordance with organic standards before they can be used in organic agriculture.

7. Cake fertilizer: rapeseed cake, cottonseed cake, bean cake, sesame cake, castor cake, tea seed cake, etc.

Mud fertilizer: uncontaminated river mud, pond mud, ditch mud, harbor mud, lake mud, etc.

What types of moles are there? Human skin tissue is composed of epidermis, dermis and subcutaneous tissue, and there are pigment cells in the skin. Due to the differences in the morphology and composition of melanin in different races, there are white, black, yellow, brown and other races. Any race can have moles. It is generally believed that the nevus cell nest originates from the melanin cells in the epidermis, and some believe that it comes from the neural crest precursor cells during the embryonic period, which gradually migrate to the surface of the skin and develop. Therefore, some moles are already present at birth, commonly known as "birth moles". What types of moles are there? According to the location of the mole in the skin, it is pathologically divided into junctional nevus, intradermal nevus and mixed nevus. These are the three most common types of moles. Junctional nevus grows in the bottom layer of the epidermis, is smooth and does not grow hair, and is more common in teenagers and less common in adults. Intradermal nevus generally grows in the dermis, is flat or nodular, can grow hair, and is more common in adults. Mixed nevus grows in the deep layer of the epidermis and the dermis, and has hair on a large area. It may be a transitional type of evolution from junctional nevus to intradermal nevus. After adulthood, the evolution tends to stagnate, so mixed nevi are rare in adults and more common in teenagers. Comparing the three types of nevi, from a pathological point of view, junctional nevi and mixed nevi may become malignant because of their junctional vitality, while intradermal nevi have no junctional vitality and generally will not become malignant. Moles that will not become malignant grow on the body all year round, without pain or itching, and are safe and sound. People will not treat them as diseases. However, moles that may become malignant should not be taken lightly. Once a pigmented nevus is transformed into a malignant melanoma, the condition is very fierce and the course of the disease progresses rapidly. It is often difficult to save lives due to late diagnosis.

What types of cats are there? There are four popular ways to classify cats: 1. Western breeds and foreign breeds. This is a widely popular classification method based on origin in the West. 2. Purebred cats and hybrid cats. Classified from the perspective of breed cultivation. 3. Domestic cats and wild cats. Classified based on living environment, but there is no strict boundary between the two. 4. Long-haired cats and short-haired cats. Mainly classified based on the length of the hair, for example, Persian cats and Himalayan cats are long-haired cats; Thai cats and Russian blue cats are short-haired cats. [Non-purebred cats] The most common cat in the world, commonly known as domestic cats. There are all kinds of colors, but most of them are bicolor. Anyway, any cat that cannot be found out is included in this category. Non-purebred cats are smart, home-loving, like to catch mice, and are kept by many people. [Abyssinian cat] Also known as the "rabbit cat", it has an elegant body, rich facial expressions, and a coat of red and yellow, which is gorgeous and extraordinary, attracting many cat lovers. Abyssinian cats are active and lively, like to move freely, but they are smart and easy to tame. They can be taught many play movements and are suitable for breeding. [Egyptian cat] It has a slightly fat and round body, short legs, and striped fur. It was worshipped as a god cat in ancient Egypt. Egyptian cats are friendly to people, lively and naughty, but more sensitive. If they are not supervised, they are easy to escape. [Long-haired cat] Long-haired cats have longer back hair, generally 5 to 10 cm long, depending on the season. Long-haired cats are larger in size, more docile in character, highly dependent, and like to be close to people. But they are easy to shed, need to be combed frequently, and are difficult to raise. [Canadian hairless cat] It has a funny and strange appearance, almost no hair on the whole body, a slender body, a slender tail like a mouse's tail, and the color is mostly gray and white. Canadian hairless cats are emotional, quiet, and kind to people, but they don't like people to hug them. Because of their strange appearance, it is rare for people to love them. [California Shiny Cat] Originated from California, USA, a hybrid cat. The body is covered with leopard spots, with golden, silver, blue, brown and other types of fur, and the appearance is very beautiful. California Spangled Cats are lively and cute, smart and healthy, sociable by nature, can get along well with other cats and even dogs, and are loyal to their owners. [Curly Cats] There are two types of cats: Cornish Rex and Devon Rex. They have slender bodies, big ears, and short, curly, wavy fur all over their bodies. They have a peculiar appearance. Curly cats are clever and naughty, enthusiastic about people, and like to play, but they are afraid of cold and difficult to raise. [Coraline Cats] Originated from Thailand, the fur color is silver-blue, also known as Thai silver cats, which are more valuable due to their rare production. The body is shorter and fatter than Siamese cats. The Coraline cat has a quieter personality, but is more alert, does not like strangers, and male cats are particularly aggressive. [American Shorthair Cats] Originated from the United States, it is a large cat breed with a strong physique. Compared with British Shorthair cats, it has a slightly longer face and mouth, and more stripes. American shorthair cats are independent, but they love home and are good at running and catching mice. They are suitable for families with yards. [Bengal cat] A cross between a small wild cat and a domestic cat. The spots on its body are different from those of other leopard-spotted cats. They are distributed horizontally, much like a rose. Bengal cats are gentle and friendly, but because of their wild cat ancestry, they are easily excited and often make irrepressible calls. [Bombay cat] A cross between a Burmese cat and an American black shorthair cat. Its coat is black and shiny, and it is large and muscular. It is called a "little black panther". Its character is the opposite of its appearance. It is quite gentle, likes to be with people, is emotional, and will purr constantly when hugged. [European shorthair cat] It looks similar to the British shorthair cat but does not have its ancestry. Its body and face are slightly longer than the British shorthair cat. Its coat is short and dense, and its texture is brittle and easy to break. European shorthair cats are alert and sensitive, have strong hunting skills, and are good at catching mice. [Scottish Fold Cat] A very beautiful and lovely cat, with a round body, head and limbs, a short and thick tail, ears that are close to the head, and large and round eyes. Scottish Fold cats are quiet, smart and tolerant, can get along with children, and are suitable for family breeding. [Exotic Shorthair Cats] Some people in China also call them "short-haired Persian cats". Except for the short hair, the other body shapes, limbs, head, face and eyes are the same as Persian cats. They are quiet and gentle, like to get close to people, but are more naughty and clever than Persian cats. [Siamese Cat] Originated in Thailand, there are also long-haired varieties in the same clan. No matter what color the coat is, the face, tail, and limbs are darker, with a long body, a long mouth and big ears. Siamese cats are very emotional, intimate and loyal to their owners, but they are emotionally unstable, like to make a lot of noise, and their calls are annoying. [Singapore cat] Small and exquisite, with strong muscles, it is a dwarf among cats. The heaviest male cat rarely weighs more than 5 kilograms. The Singapore cat is active and playful, curious, likes to burrow around, and even crawls into the sewer, so it is not loved by people. [British Shorthair Cat] The British Shorthair Cat has a long history, but it was not until the early 20th century that it attracted people's love. The cat has a plump body, short and well-developed limbs, short and dense fur, a big head and a round face, and large and round eyes that show various colors according to the different fur. The cat is gentle and calm, friendly to people, and very easy to raise.

Adopt it

What types of horses are there? Mongolian horse, Kazakh horse, Hequ horse, Southwest horse, Sanhe horse, Yili horse, Dutch warmblood horse, Barb horse

About Mongolian Horses

The Mongolian horse is one of the oldest horse breeds in China and even in the world. It is mainly produced in the Inner Mongolia grasslands and is a typical grassland horse breed. The Mongolian horse is not big in size, with an average height of 120 to 135 cm and a weight of 267 to 370 kg. It has a sturdy body, strong limbs, a rough and solid physique, a large head and a wide forehead, a deep and long chest, short legs, and well-developed joints and tendons. The coat is dense and the color is complex. It is hard-working, not afraid of cold, can adapt to extremely extensive feeding and management, has strong vitality, and can survive in harsh and difficult conditions. It has always been a good military horse.

About Kazakh Horse

The Kazakh horse from Xinjiang is also a steppe horse breed. Its morphological characteristics are: a medium-sized, delicate head, short ears, a slender neck, a slightly raised neck, a high forearm, a narrow chest, and hind legs that are often knife-shaped.

About Hequ Horse

Hequ horse is also an ancient and excellent local horse breed in China. It was often used as tribute in history. It originated in the grasslands at the junction of Qinghai, Gansu and Sichuan provinces in the upper reaches of the Yellow River. Because it is located in the winding Yellow River, it is named Hequ horse. It is the largest and most excellent horse among the local breeds in China. Its average height is 132 to 139 cm and its weight is 350 to 450 kg. The head of Hequ horse is slightly larger, the nose bridge is slightly rabbit-shaped, the neck is wide and thick, the trunk is straight, the chest is deep and wide, and the body is sturdy, which has absolute advantages as a draft horse.

About Southwest Horse

Southwestern horses are distributed in Sichuan, Yunnan, Guizhou and Guangxi. They are small in size and good at walking on mountain roads. They have large heads, high necks, and long manes, tails and manes. They have good body structure, well-developed tendons and solid hooves. They are good at climbing mountains and can carry more than 100 kilograms of goods and travel 30 to 40 kilometers a day. They are a much-needed transportation force in the mountainous areas of the southwest.

What types of pumps are there? There are clean water pumps, sewage pumps, vacuum pumps, and air pumps.

This is divided by medium

There are many other differences between centrifugal and non-centrifugal structures, which I cannot list in the following.

The valve switches are controlled by changing from normally open to normally closed or from normally closed to normally open.

Usually equipped with a PLC or other things to control

The signal is adjusted according to the switching conditions you need.

Equipment failure can be judged from the water volume and motor. It is also possible that the pump impeller is broken.

What are the types of flour commonly used?

1. Wheat flour, which is the most common white flour in the home, is the main flour raw material for making pasta. Flour on the market is divided into high-gluten flour, medium-gluten flour and low-gluten flour according to the gluten strength of the flour. High-gluten and medium-gluten flour are generally used to make noodles, dumplings, buns, etc.; low-gluten flour is generally used to make cakes, shortbread, etc.

2. Corn flour. Corn flour is generally used to make cornmeal cakes, steamed bread, steamed cakes and other staple foods. It can also be used to make corn bread, dumplings, etc. It is generally difficult to shape corn flour alone, and it needs to be mixed with ordinary white flour.

3. Buckwheat flour. Buckwheat flour is generally used to make hand-rolled noodles, knife-cut noodles, etc.

4. Soybean flour. Soybean flour is usually mixed with wheat flour to make soybean noodles, etc.

These are probably the types mentioned above, of course the actual types of flour are far more than these.

What are the types of motors? They can be divided into two categories, one is brushed and the other is brushless. Brushless motors are divided into brushless gearless and brush with gear. Brushless motors are divided into brushless gearless and brushless with gear and brushless Hall gearless motors. Common motors include: brush geared hub motor, brushless geared hub motor, brushless geared hub motor, brushless gearless hub motor, side-mounted motor, etc.

What types of fish are there? my country has abundant freshwater fish resources, and with artificial breeding, the market supply is sufficient. Among them, carp, silver carp, grass carp, and black carp are the most common, in addition to eels, turtles, etc.

Carp is a kind of fine freshwater fish. Its scales are white with metallic luster, it has a red tail, tender meat and delicious taste. The Yellow River carp is especially popular.

Grass carp is also called grass green, with a tea yellow body color. It is the most productive freshwater fish. This fish is characterized by fast growth, heavy weight, big head and fat meat, but the meat is coarse and of lower quality than carp.

Silver carp is divided into two types: silver carp and bighead carp (commonly known as fathead fish). Silver carp has a white body color, small scales, a large head, fat meat, and delicious taste. The head is the fattest, especially suitable for making casserole fish head.

Crucian carp is also called crucian carp. It has a flat and wide body, a prominent back bulge, and small scales. It is characterized by tender meat and great flavor, but it has many small bones. Crucian carp is most suitable for boiling soup. Small crucian carp is suitable for making crispy fish.

Black carp, also known as blackfin, has a long, cylindrical body, a black spine, a milky white belly, and white, plump flesh. It is one of the freshwater fish with the most tender meat. It contains a lot of fat, especially the meat from the pectoral fin and the head and tail. The black carp's lung is the most tender part of the fish body and contains a lot of fat. The famous dish "Roasted Bald Lung" is made with black carp lungs. It is cooked and eaten hot, and is extremely delicious.

The eel, also known as long fish and yellow eel, has a long and thin body, a thick head and a thin tail, a dark-brown back, a yellow belly, small eyes and no scales. The meat of this fish is extremely tender and delicious, and is regarded as a top-quality fish.

The soft-shelled turtle, also known as the turtle fish, has tender meat and rich nutrition, and is a high-end tonic.

Ornamental fish refers to those fish with bright colors or peculiar shapes that have ornamental value. They are usually composed of three major strains, namely temperate freshwater ornamental fish, tropical freshwater ornamental fish and tropical marine ornamental fish.

Temperate freshwater ornamental fish mainly include red crucian carp, Chinese goldfish, and Japanese koi. There are three major series of tropical freshwater ornamental fish: the first is the lantern species, the second is the angelfish, and the third is the dragon fish. Marine ornamental fish mainly come from the coral reef waters of the Indian Ocean and the Pacific Ocean. They are of many varieties and strange colors, with a primitive, simple and mysterious natural beauty.

Raising goldfish is one of the common hobbies of people. Since the late 1980s, the ornamental fish market has gradually expanded in Guangzhou. At that time, almost every household had a fish tank. A "lion head" goldfish ranged from tens to hundreds of yuan, showing its noble origin. However, goldfish are difficult to raise, have a low survival rate and complicated procedures. The number of fish farmers has gradually decreased. The aquarium market has focused on cultivating high-quality fish species, which has also made the price of noble goldfish higher and higher. Koi became a goldfish star in the early 1990s. An expensive koi sold for thousands of yuan, and there were also varieties that sold for tens of thousands of yuan. Influenced by Hong Kong and Taiwan, dragon fish became famous overnight after koi, and those with superior shape and color sold for more than 30,000 yuan. But in recent years, the prices of koi and red dragon have fallen back to a relatively stable level. An adult red dragon with excellent body shape, scale color and posture sells for no more than 10,000 yuan.

At present, the newcomers in the aquarium market are the "flower arowana" from Malaysia and the "fluorescent fish" from Taiwan. The "status" of koi and dragon fish has been replaced by the "flower arowana". The price of high-quality species remains above 10,000 yuan, and there are also rare species with a price tag of more than 100,000 yuan. The "fluorescent fish" is a new species introduced at the beginning of this year. This fish can emit weak fluorescence in a dark environment. The price of a small fish less than two centimeters long is as high as 90 yuan. The existing fish are divided into two major categories: cartilaginous fish and bony fish. Fish are the oldest vertebrates. They live in almost all aquatic environments on the earth - from freshwater lakes and rivers to saltwater seas and oceans. There are about 24,000 species of fish in the world. Two-thirds live in seawater, and the rest live in freshwater. There are 2,500 species in China, of which more than 100 can be used for medicinal purposes. Common medicinal animals include seahorses, sea dragons, eels, carp, crucian carp, sturgeons (swim bladder is fish bladder glue), large yellow croaker (otolith is fish brain stone), sharks, etc. In addition, they are often used as raw materials in the pharmaceutical industry. For example, the liver of cod, shark or ray is the main raw material for extracting cod liver oil (vitamin A and vitamin D). Hydrolyzed protein, cytochrome C, lecithin, cephalin, etc. can be extracted from various fish meats. The liver and ovaries of the river contain a large amount of tetrodotoxin, which can be extracted to treat neuropathy, spasms, tumors and other diseases. The bile of large fish can be used to extract "bile pigment calcium salt", which is the raw material for artificial production of bezoar. Fish live in seawater or freshwater for their entire lives, and most of them have a body shape and fins suitable for swimming. They breathe with gills and hunt with upper and lower jaws. A beating heart has appeared, which is divided into one atrium and one ventricle. The blood circulation is a single cycle. The appearance of the spine and head has made the fish class evolve into a vertebrate that is best adapted to life in water. This is because water has different depths and the pressures in different places are different. The sea level is 1 atmosphere, while the deep sea area can reach 1000 atmospheres. The salt content of fresh water and sea water ranges from 0.001 to 7% from fresh water to salt water. In addition, the temperature difference and oxygen content of water vary greatly depending on the geographical environment. Due to the diversity of these water areas, water layers, water quality, biological factors and non-biological factors in the water, the body structure of fish has undergone different changes to adapt to different changes in the outside world. It is more advanced than the Cyclostomata. The fish class is the largest class in the existing vertebrate subphylum. From the perspective of animal evolution, this class is the beginning of jawed fish, so it is the most primitive and oldest class of jawed fish. This is the largest classification group in the vertebrate subphylum. As early as the Devonian period, many marginal branches have been derived, and they have developed and evolved into fish of various complex shapes. Existing fish are divided into cartilaginous fish and bony fish. 1. Chondrichthyes This system is the lowest level of existing fish, with more than 200 species in the world and more than 140 species in my country, most of which live in the sea. Its main characteristics are: ① No hard bones throughout life, the internal skeleton is composed of cartilage. ② Most of the body surface is covered with J scales. ③ The gill interval is well developed and there is no gill cover. ④ Crooked tail fin. This system is divided into two subclasses, namely the Elasmobranch and Holocephalus. 2. Osteichthyes The Osteichthyes is the most numerous type of existing fish in the world, with more than 20,000 species, most of which live in marine waters and some live in fresh water. Its main characteristics are: ① The skeleton is hardened to hard bones to varying degrees. ② The body surface is covered with hard scales, round scales or comb scales, and a few species are degenerate and scaleless. The mucous glands of the skin are well developed. ③ The gill septum is partially or completely degenerate, the gills do not open directly to the outside of the body, and are protected by bony gill covers. The water flowing out of the gill slits is discharged through the rear edge of the gill cover, and most have swim bladders. ④ The fish tail is often a normal tail, but there are also primitive tails or crooked tails. ⑤ Most are fertilized externally and oviparous, and a few have metamorphosis during development. The earliest fish was a round-mouthed, jawless fish that appeared on Earth during the Cambrian period 450 million years ago. Fish are easily distinguished from their appearance. They form the largest group of vertebrates: among a total of 50,000 vertebrates, there are more than 22,000 species of fish. Not all animals that live in water are fish. For example, whales are mammals. However, all fish can adapt well to life in water. They use fins to move. Fish have two pairs of fins - pectoral fins and pelvic fins, located on both sides of the body; there is also a caudal fin that grows on the tail; and depending on the species, there are one or two dorsal fins on the back and one anal fin on the buttocks. They have a gas-filled sac called a swim bladder, which enables fish to sink, float and maintain their position in the water. Only rays and sharks lack this organ. Fish also have gills for breathing, which are covered by operculum in most species. The gills are located on either side of the head, behind the mouth, and are used to filter the water swallowed through the mouth, extract oxygen from the water, and then expel the water through openings called gill slits. The size of different species of fish varies greatly. Their bodies are composed of 3 parts: the head, the trunk and the tail. The skin is covered with scales, which vary in size and number. There is a distinct line on each side called the lateral line, which is a sensory organ and is used to determine direction. The muscles of some bony fish are separated by some tiny bones. The first fish to appear on Earth had a round, jawless mouth, and only 70 species of such fish exist today, forming the jawless fish. Among these fish, the lamprey is the most famous, which has no scales and a slender body with a rounded shape, much like an eel. Lampreys attach themselves to other fishes with a mouth that has a suction cup and feeds on the host's blood. Other fish are divided into two major groups: bony fish and cartilaginous fish. Bony fish have a skeleton. This group includes primitive bony fish, which have only a portion of their skeleton made of bone. Examples include lorises (including the coelacanths), lungfish, and sturgeons (such as sturgeons), which differ from more advanced bony fish in that their skeletons are made entirely of bone. Moray eels, soles, and crappies are representatives of bony fish, which have a variety of appearances, but all have a very symmetrical tail fin covered with tiny scales (with a few exceptions, including eels and some carp). Bony fish are divided into several groups. Anguilla are fish whose larvae look very different from the adults. Herring are fish that live in groups. Carp include almost all freshwater fish. Perch and tuna are fish whose tail fins are supported by hard spokes. They are called "spiny-finned fish" and form the largest group of bony fish. Cartilaginous fish have a skeleton made entirely of cartilage, reinforced with calcium. This group of fish is mainly sharks and rays. Eels are born as small, flat-bodied fish called "young eels". When they mature, they have a long, smooth body, usually scaleless, with a continuous fin along their back. Eels live in rivers and lakes in Europe and America, and they migrate to the Sargasso Sea northeast of the West Indies in the North Atlantic Ocean, where they breed. They die after the young are born. The young eels take on their adult form on their way back across the Atlantic Ocean, and they also begin to give birth in the Sargasso Sea on their way back. Herrings live in the North Sea, the English Channel, and the Baltic Sea. Adults have a light-colored belly and a dark blue or nearly black back. Like sardines and sprats, they live in schools, sometimes with thousands of fish living together. This is an effective method of self-defense for each fish, because a predator can only choose one target among many. When attacked, the school of fish disappears almost immediately. There are thousands of species of fish belonging to the carp family, which are almost universal. These freshwater fish have large scales and their teeth are not fixed in the jaws but in the throat. Their mouths can be moved forward to suck up food. Many species of the genus Cyprinus live mainly in calm rivers, small ponds and lakes in Asia and Europe. The shape and color of each species vary greatly. Some species have only a few large scales (mirror carp) or almost no scales (grass carp). These fish are easy to farm, and farmers have created many varieties. Carp mainly feed on plants and invertebrates. The spawning season depends on the water temperature, which should not be too cold (at least 20°C). Female fish produce hundreds or thousands of eggs, but most of the small fry become food for other fish and even adult carp as soon as they are born. Spiny-finned fish appeared about 60 million years ago. The perch is a typical example of this type of fish, with fins supported by hard, sharp spokes and a large tail fin with spines. Perches live in lakes and rivers in Europe and North America, eating invertebrates and small fish, including their own young. Other species of these fish live in the ocean, such as tuna and swordfish, which are powerful swimmers that can swim up to 100 kilometers per hour. Tuna can weigh up to 500 kilograms and are carnivorous. They are unique among fish in their ability to maintain a body temperature higher than the water temperature, and their species include albacore tuna in the Pacific and bluefin tuna in the Mediterranean and Atlantic. Sharks and rays are the main representatives of modern cartilaginous fish, which may have appeared 410 million years ago. As their name suggests, they have a skeleton made of cartilage. Cartilage is a flexible material that hardens when filled with calcium and is solid like bone. Cartilaginous fish grow in large numbers in temperate and hot oceans. They breathe in water using gills. The gills communicate directly with the outside world through several gill slits at the back of the head. There are about 550 species of cartilaginous fish, of which 370 are sharks, and the rest are basically flat-bodied skates and electric rays.

What types of certificates are there? 1: General certificates: such as computer level certificates, College English Test Band 4 and Band 6 certificates, and College English Test Band 4 and Band 6 oral certificates. Although most schools have cancelled the regulations linking these certificates to degrees, they are still valued by employers, and therefore have become the first choice for college students to obtain certificates. 2: English proficiency certificates: such as TOEFL score certificates, IELTS score certificates, intermediate and advanced English interpretation qualification certificates, etc. This type of exam requires strong English listening, speaking, reading and writing skills, and is the primary target for college students who plan to study abroad and work in foreign companies. 3: IT proficiency certificates: such as the National Computer Software Professional and Technical Qualification and Level Certificate, ACCP Software Engineer, Microsoft System Administrator (MCSA) Certificate, etc. As computers and networks play an increasingly important role in work, high-quality IT skills have often become a "sharp weapon" for job seekers. 4: Professional qualification certificates: such as customs broker certificates, document clerk certificates, logistics engineer qualification certificates, national judicial examination certificates, tour guide qualification certificates, civil servant certificates, etc. The main qualification certificates have the widest range and the most types.