Bài 5. Một số bài tập khác 1. Cho A=4+4^2+4^3+...+4^23+4^24 . Chứng minh: A chia hết 20; A chia hết 21; A chia hết 420 . 2. Tìm số tự nhiên n để hai số sau nguyên tố cùng nhau: a) n + 2 và n + 3 b) 2n + 1 và 9n + 4. 3. Tìm các số tự nhiên a, b biết: a) a + b = 192 và ƯCLN(a, b) = 24. b) 0 < a < b, a + b = 42 và BCNN(a, b) = 72. 4. Tìm số tự nhiên nhỏ nhất sao cho số đó chia 3 dư 2, chia cho 5 dư 3, chia cho 7 dư 4. 5. 5.1. Tìm số nguyên x, biết: a) 2x – 1 là bội của x – 3; b) 2x + 1 là ước của 3x + 2. 5.2. Tìm số nguyên x, y sao cho: a) (2x – 1)(y 2 + 1) = -17; b) (3 – x)(5 - y) = 2; c) x.y = 18; x + y = 11.
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Mark the letter A, B, C, or D on your answer sheet to indicate the word those underlined part differs
from the other three in pronunciation in each of the following questions
1. A. Sugar B. singer C She D. . Fish
2. A. busy B. bus C. number D. study
3. A. peaceful B. pleasure C. sleepy D. cheap
4. A. store B. sister C. factory D. picture 5. Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the
following questions. - Phong Nha- Ke Bang in Quang Binh is one of______ in the world. A. nature wonder B. natural wonders C. wonderful nature D. wonder nature 6. Look! The girls _________ in the hall. A. are dancing B. dance C. dances D. dancing 7 There are too many buildings………………… this city. A. in B. at C. with D. on 8. In the cinema we eat or drink anything. A. must B. should C. shouldn't D. can 9. Would you like _________ milk in your coffee? A. any B. some C. a D. a few 10. Do you know ________people in this neighbourhood?. A. much B. a little C. many D. little 11. I must __________ this homework today. A. finish B. finishes C. finishing D. to finish 12. The weather is very hot in______. You can see camels there. A. valley B. ocean C. desert D. mountain 13. __________ your parents give you pocket money? A. Do B. Are C. Does D. Is 14. My brother can do all difficult Math exercises. He is a(n) __________ student. A. hard-working B. careful C. boring D. smart 15. Lan is ……………..…....at English than my sister. A. good B. better C. best D. the best 16. We …………..keep quiet in the library so that everyone can enjoy reading books. A. should B. shouldn’t C. can D. can’t 17. “Bye” - “_____” A. See you lately. B. Thank you. C. Meet you again. D. See you later. 18. “Hello! My name is Phuong. Nice to meet you!” “Hello! _____ ” A. That’s fine. B. Really? C. Good. D. I’m Susan. Pleased to meet you 19. There aren’t some boy students in my class now. A. B. C . D. Question 20 .The countryside is beautifuller than the town centre. A. B. C . D. 21. Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) CLOSEST in meaning
to the underlined word(s) in each of the following Question - It’s very difficult for me to study English well. A. hardB. important C. easyD. boring 22. My hometown is very peaceful. A. noisy B. quiet C. crowded D. narrow 23. Mark the letter A, B, C or D to indicate the word(s) OPPOSITE in meaning
- This house is so old. A. newB. nice C. big D. small 24. The streets here are narrow. A. big B. clean C. darkD. wide 25. Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the
correct answer to each of the questions.
3 Tet or Lunar New Year holiday is very important for Vietnamese people. Tet is a festival which happens in late January or early February. Before Tet, people usually clean and decorate their homes. They go to the market to buy candy, jams or dried water melon seeds. They also wear new beautiful clothes at Tet. They often buy peach blossoms and marigolds which are traditional flowers on Tet holiday. Tet is time for family members to gather and have some special meals with special food such as sticky rice cakes. People often visit relatives and close friends on the second day of the holiday. - When does Tet happen? A late January or early February B.May C. April D June 26. Do they buy any candy and jams? A Yes , they do . b . No , they don’t C .Yes , they are No, They aren’t 27. What do they usually do on Tet holiday? A. Nothing B .They play games C. visit neighbours D. clean and decorate their homes 28.Which day of the holiday do people often visit relatives and close friends? A. the first of year B.The second day of the holiday C. the third of year D. The last of year
29. Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the
correct answer to each of the questions from 29 to 32 Ha Long Bay is in Quang Ninh Province. It has many (29) …… and caves. The islands are named after things around us. (30) …… the Bay you can find Rooster and Hen Island and even Man’s (31) …… Island. You must take a boat ride around the islands – it’s essential! Tuan Chau is (32) …… island in Ha Long Bay. There you can enjoy great Vietnamese seafood. You can watch traditional dances. You can join exciting activities . Ha Long Bay is Vietnam’s most beautiful natural wonder. A. rocks B. islands C. island D. lakes 30. A. On B. At C. In D. Over 31. A. arm B. leg C. head D . nose 32. A. the biggest B. big C. biggest D. bigger
33. Mark the letter A, B, C, or Don your answer sheet to indicate the sentence that is closest in
meaning to the sentence given in each of the following questions.
- I don't have a bookshelf in my room. A. There isn't a bookshelf in my room. B. There is a bookshelf in my room.
4 C. There isn't a in my room bookshelf. D. There isn't bookshelf in a my room.
34. How about going to the cinema at the weekend. A. Let's to go to the cinema at the weekend. B. Let's going to the cinema at the weekend. C. Let's go to the cinema at the weekend. D. Let's goes to the cinema at the weekend
34. My mother is taller than me A.I am as tall as my mother B.I am not so tall as my mother C.I am taller than my mother D. I am short than my mother 36. Mai has a notebook and it's on the table. A. Mai is notebook is on the table. B. She's notebook is on the table. C. she is notebook is on the table. D. Mai's notebook is on the table
37. “There are four people in my famiy “. A. My family is a big family. B. My family doesn’t have many people C. My family has four people D. My family has more than four people
38. “What subject do you like? “ A. What’s your like subject? B. What’s your favorite subject? C. What your favorite subject? D.What subject is your favourite ?
39. John’s hair is curly and blond. A. John has blond curly hair.
5 B. John’s hair has yellow color. C. John has curly blond hair. D. John has hair blond curly.
40. My mom wears Ao dai on Tet holiday A. My mom washes Ao dai on Tet holiday B. My mom dresses up Ao dai on Tet holiday C. My mom makes Ao dai on Tet holiday D. My mom buys Ao dai on Tet holiday
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