2022年大学英语四级模拟试题附答案

1、最新大学英语四级模拟试题（一）Part Writing (30 minutes)Directions: For this part, you are allowed 30 minutes to write a short essay entitled The Popularity of Getting Certificates on Campus. You should write at least 150 words following the outline given below.1.大学校园内多种证书旳报考十分火热2.大学生考证旳利弊3.考证面前，我旳选择The Popularity

2、of Getting Certificates on CampusPart Reading Comprehension (Skimming and Scanning) (15 minutes)Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions on Answer Sheet 1.For questions 1-7, choose the best answer from the four choices marked A), B),

3、C) and D). For questions 8-10, complete the sentences with the information given in the passage.Main Energies for the BodyA balanced diet is one that provides an adequate intake of energy and nutrients for maintenance of the body and therefore good health. A diet can easily be adequate for normal bo

4、dily functioning, yet may not be a balanced diet.CarbohydratesCarbohydrates are a rapid source of energy, they are the body's fuel. The bulk of a balanced diet should be made from carbohydrates. If eaten in an excess of the dietary requirements carbohydrates are easily stored as fats in the cell

5、s, although carbohydrate is the first source of energy in the body. An average adult requires about 12,000kJ of energy a day, most of this is supplied by the respiration of carbohydrates in the cells.Carbohydrates are used principally as a respiratory substrates, i.e. to be oxidized to release energ

6、y for active transport, macromolecule synthesis, cell division and muscle contraction. Carbohydrates are digested in the duodenum and ileum and absorbed as glucose into cells. Sources of carbohydrates such as starch are rice, potatoes, wheat and other cereals. Sugars are also carbohydrates, sources

7、of sugars are refined sugar - sucrose, which is a food sweetener and preservative and fruit sugars - fructose. If the diet lacks carbohydrate stores of fat are mobilized and used as an energy source.ProteinsProtein is not a direct source of energy in the body, it is used primarily for growth and rep

8、air of body tissues while remaining an energy source as a last resort. Proteins fulfill a wide variety of roles in the body. They are broken down in the stomach and intestines to amino acids which are then absorbed. The body can only form 8 amino acids to build proteins from, the diet must provide E

9、ssential Amino Acids (EAAs) which are synthesized into proteins which can be structural, i.e. collagen in bone, keratin in hair, myosin and actin in muscle; metabolic enzymes, hemoglobin, protective antibodies and communicative hormones.Sources of protein include meat, fish, eggs and pulses. The die

10、t needs to provide 8 EAAs as the body is unable to synthesis proteins without these molecules. 2 other amino acids are synthesized from EAAs so if the diet lacks the original EAAs these other two will not be present either. Phenylalanine is converted to tyrosine and methionine is converted to cystei

11、ne. Cells draw upon a pool of amino acids for protein synthesis which either come from dietary protein digested and absorbed in the gut and the breakdown of body protein such as muscle. However, unlike fats and carbohydrates there is no store of amino acids for cells to draw on, any amino acid in ex

12、cess of immediate bodily requirements is broken down into urea and excreted. It is therefore important to maintain the dietary intake of protein everyday. If the body lacks protein, muscle wasting occurs as muscle is broken down.If protein is lacked in a diet a person develops kwashiorkor which is c

13、aused when high levels of carbohydrates are eaten to overcome the lack of protein in the diet. One symptom of kwashiorkor is the abnormal collection of fluid around the abdomen due to the lack of protein in the blood. The body cannot retain water by osmosis and fluid accumulates in tissues causing t

14、hem to become waterlogged.Vitamin CategoriesVitamins cannot be synthesized by the body so must be supplied by diet. Vitamins have no common structure or function but are essential in small amounts for the body to be able to utilize other dietary components efficiently.Vitamins fall into two categori

15、es, fat soluble vitamins such as vitamin A, D, E and K which are ingested with fatty foods and water soluble vitamins such as the B group vitamins and vitamin C. Vitamins are known as micronutrients because only small quantities are required for a healthy diet, in fact fat soluble vitamins can be to

16、xic in high concentrations, for example the body stores vitamin A, or retinol, in the liver as it is toxic if kept in high concentrations in the blood stream, a dose of more than 3300mg of vitamin A can be considered toxic. Water soluble vitamins such as vitamin C and B groups vitamins can be excret

17、ed in the urine if in excess in the diet.Vitamins AVitamin A is essential to the proper functioning of the retina in the eye and the epithelial tissues. A lack of vitamin A results in dry, rough skin, inflammation of the eyes, a drying or scarring of the cornea - xerophthalmia, which occurs when the

18、 secretion of lubricating tears is stopped, the eyelids become swollen and sticky with pus. Mucous surfaces of the eye may become eroded allowing infection to set in, leading to ulceration and destruction of the cornea. Night blindness - an inability to see in dim light can also occur. Rod cells in

19、the retina of the eye detect light of low intensity, they convert vitamin A into a pigment, rhodopsin, which is bleached when light enters the eye. Rod cells resynthesis rhodopsin, but if there is a deficiency of the vitamin, rod cells can no longer function and the result is night blindness. Epithe

20、lial cells use retinol to make retinoic acid, an intracellular messenger used in cell differentiation and growth. Without retinoic acid epithelial cells are not maintained properly and the body becomes susceptible to infections, particularly measles and infections of the respiratory system and gut.X

21、enophthalmia is common among children who's diets consist of mainly cereals with little meat or fresh vegetables, this is common in Indonesia, Bangladesh, India and the Philippines.Vitamins DVitamin D, or calciferol, is another fat soluble steroid vitamin which functions to stimulate calcium upt

22、ake from the gut and its deposition in bone. vitamin D acts as a hormone when converted by enzymes in the gut and liver into an active form of "active vitamin D", which stimulates epithelial cells in the intestine to absorb calcium. vitamin D is therefore essential in growing children'

23、s diets to enable the growth of strong bones. Without adequate amounts of vitamin D children can develop rickets, which is the deformation of the legs caused when they lack calcium to strengthen the bones. In adults a lack of vitamin D in the diet can lead to osteomalacia, a progressive softening of

24、 the bones which can make them highly susceptible to fracture.Vitamin D is made by the body when exposed to sunlight and is stored in the muscles, however, if the skin is rarely exposed to the sunlight or is dark little vitamin D is produced. Foods such as eggs and oily fish are all rich in vitamin

25、D.Vitamins KVitamin K, phylloquinone, is found in dark green leafy vegetables such as spinach and kale. It is a fat soluble vitamin which is involved in the clotting process of blood. In the intestines bacteria synthesize a number of important clotting factors which need vitamin K. Without vitamin K

26、 cuts can fail to heal and internal bleeding can occur.Vitamins CVitamin C is a water soluble vitamin, known chemically as ascorbic acid. It is found in citrus fruits such as oranges and lemons, and also in potatoes and tomatoes. The main function of vitamin C is the formation of connective tissues

27、such as collagen. It is also known to be an antioxidant which helps to remove toxins and aids the immune system. A lack of vitamin C leads to Scurvy, a condition experienced by sailors on long journeys when they did not have fruit in their diets. Scurvy causes painful, bleeding gums. As vitamin C is

28、 water soluble, it is not toxic in high doses as it can be excreted in the urine, very high doses can however cause diarrhea.Vitamins BB group vitamins have a wide range of roles acting as co-enzymes in metabolic pathways. They are found in most plant and animal tissues involved in metabolism, there

29、fore foods such as liver, yeast and dairy products are all rich in B group vitamins. Deficiency of B group vitamins include dermatitis, fatigue and malformation of red blood cells.1. An adult needs about 12,000kJ of energy a day from _.A. the cell B. the respiring process of carbohydratesC. fats in

30、the cell D. a balanced diet2. Carbohydrates are ultimately absorbed into cells in the process of _.A. digestion B. respirationC. oxidization D. mobilization3. The Essential Amino Acids which build part of proteins can be obtained from_.A. stomach B. body tissuesC. the body D. the diet4. The ultimate

31、 cause of kwashiorkor is lack of _.A. protein B. carbohydratesC. vitamins D. diet5. Vitamins are called “micronutrients” in that _.A. excessive fat soluble vitamins can be excreted in the urine B. the body only requires small amount of vitaminsC. a dose of 3300mg of vitamins can be considered toxic

32、D. the high concentrations of water soluble vitamins are toxic6. Night blindness is a disease normally caused by lack of _.A. fat soluble vitamins B. water soluble vitaminsC. vitamin A D. innate disability7. The main function of vitamin D is to prevent adults from _.A. the growth of strong bones B.

33、fractureC. a progressive softening of the bones D. calcium uptake from the gut8. Although the human body produces vitamin D normally, it fails to do so if there is not enough _.9. The reason why vitamin C is seen as an antioxidant is that it drives _ out of the body.10. If you are in lack of B group

34、 vitamins, you should turn to _.Part III Listening Comprehension (35 minutes)Section ADirections: In this section, you will hear 8 short conversations and 2 long conversations. At the end of each conversation, one or more questions will be asked about what was said. Both the conversation and the que

35、stions will be spoken only once. After each question there will be a pause. During the pause, you must read the four choices marked A), B), C) and D), and decide which is the best answer. Then mark the corresponding letter on Answer Sheet 2 with a single line through the centre.11. A) He thinks hes

36、very organized.B) He doesnt want to join the display.C) He doesnt think he should lead the study group.D) He knows someone who can lead the study group.12. A) He doesnt know where his brother keeps his computer.B) The woman should buy a used computer.C) He doesnt know how much computers cost.D) His

37、brother paid too much for the computer.13. A) Its been to warm to wear the jacket.B) The jacket is too big for him.C) He doesnt like cold weather.D) He didnt buy the jacket until cooler weather arrived.14. A) He started the semester in a bad mood.B) Hes not usually bad-tempered.C) He has few respons

38、ibilities.D) He doesnt like the man.15. A) He forgot to cancel the reservation.B) They can go to the restaurant after the woman has finished working.C) He has to work late tonight.D) They dont have a reservation at the restaurant.16. A) Use bleach on his socks.B) Buy new white socks.C) Wash his red

39、T-shirt again.D) Throw away his pink socks.17. A) He isnt satisfied with his progress.B) He wants to move up more quickly than hes presently doing.C) He has advance quickly enough in his career.D) He feels frustrated as he tries to move up the ladder.18. A) Try on a smaller sweater.B) Look for anoth

40、er style at a different store.C) Give the sweater away as a gift.D) Exchange the sweater for a bigger one.Questions 19 to 22 are based on the conversation you have just heard.19. A) She's unable to attend the study session.B) She has seen a doctor recently.C) She's concerned about medical ca

41、re.D) She mentions the need for some medical tests.20. A) To improve the study skills of university students.B) To suggest changes in the student government.C) To give people the opportunity to speak with a politician.D) To discuss graduation requirements for political science majors.21. A) Graduate

42、 school application procedures.B) Funding for university education.C) Winning the confidence of voters.D) Preparing for an important test.22. A) Tell her what to study for the history test.B) Write a favorable letter of recommendation.C) Advise her about how to run an election campaign.D) Suggest a

43、topic for a research paper.Questions 23 to 25 are based on the conversation you have just heard.23. A) Boston schools.B) Frontier life.C) Teaching requirements.D) Immigration patterns.24. A) She was a famous author.B) Her family later became famous landowners.C) She exemplifies the immigrant spirit.

44、D) She invented some labor-saving farm equipment.25. A) To the library.B) To the movies.C) To a bookstore.D) To a travel bureau.Section BDirections: In this section, you will hear 3 short passages. At the end of each passage, you will hear some question. Both the passage and the questions will be sp

45、oken only once. After you hear a question, you must choose the best answer from the four choices marked A),B),C),and D). Then mark the corresponding letter on the Answer Sheet with a single line through the center.Passage OneQuestions 26 to 29 are based on the passage you have just heard.26. A) They

46、 were drawing pictures. B) They were watching TV.C) They were making a telephone call. D) They were tidying up the drawing room.27. A) They locked the couple up in the drawing room.B) They seriously injured the owners of the house.C) They smashed the TV set and the telephone.D) They took away sixtee

47、n valuable paintings.28. A) He accused them of the theft.B) He raised the rents.C) He refused to prolong their land lease.D) He forced them to abandon their traditions.29. A) They wanted to protect the farmers interests.B) They wanted to extend the reservation area for birds.C) They wanted to steal

48、his valuable paintings.D) They wanted to drive him away from the island. Passage TwoQuestions 30 to 32 are based on the passage you have just heard.30. A) Through food. B) Through air.C) Through insects. D) Through body fluids.31. A) They ran a high fever. B) They died from excessive bleeding.C

49、) Their nervous system was damaged. D) They suffered from heart-attack.32. A) To see what happened to the survivors of the outbreak.B) To study animals that can also get infected with the disease.C) To find out where the virus originates.D) To look for the plants that could cure the disease.Passage

50、ThreeQuestions 33 to 35 are based on the passage you have just heard.33. A) To determine whether the Earths temperature is going up.B) To study the behavior of some sea animals.C) To measure the depths of the ocean.D) To measure the movement of waves in the ocean.34. A) They were frightened and dist

51、ressed.B) They swam away when the speaker was turned on.C) They swam closer to “examine” the speaker when it was turned off.D) They didnt seem to be frightened and kept swimming near the speaker.35. A) To attract more sea animals to the testing site.B) To drive dangerous sea animals away from the te

52、sting site.C) To help trace the sea animals being tested.D) To determine how sea animals communicate with each other.Section CDirections: In this section, you will hear a passage three times. When the passage is read for the first time, you should listen carefully for its general idea. When the pass

53、age is read for the second time, you are required to fill in the blanks numbered from 36 to 43 with the exact words you have heard. For blanks numbered from 44 to 46 you are required to fill in the missing information. For these blanks, you can either use the exact words you have just heard or write

54、 down the main points in your own words. Finally, when the passage is read for the third time, you should check what you have written.Part IV Reading Comprehension (Reading in Depth) (25 minutes)Section ADirections: In this section, there is a passage with ten blanks. You are required to select one

55、word for each blank from a list of choices given in a word bank following the passage. Read the passage through carefully before making your choices. Each choice in the bank is identified by a letter. Please mark the corresponding letter for each item on Answer Sheet 2 with a single line through the

56、 centre. You may not use any of the words in the bank more than once.Questions 47 to 56 are based on the following passage.Dreams are a way for the subconscious to communicate with the _47_ mind. Dreaming of something youre worried about, researchers say, is the brains way of helping you rehearse fo

57、r a disaster in case it occurs. Dreaming of a challenge, like giving a presentation at work or playing sports, can enhance your _48_. And cognitive neuroscientists have discovered that dreams and the rapid eye movement (REM) that happens while youre dreaming are _49_ to our ability to learn and remember. Dreaming is a “mood regulatory system,” says Rosalind Cartwright, PhD, chairman of the psychology _50_ at Rush University Medical