Một loài sinh vật có bộ NST 2n. Trong quá trình giảm phân, bộ NST của tế bào không phân ly, tạo thành giao tử chứa 2n. Khi thụ tinh, sự kết hợp của giao tử 2n này với giao tử bình thường (n) sẽ tạo ra hợp tử có thể phát triển thành: A. Thể tam bội B. Thể đơn bội C. Thể tự bội D. Thể lưỡng bội

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I Find the word which has a different sound in the part underlined. 1. A. answer B. further C. butter D. birth 2. A. burn B. collect C. alone D. neighbour 3. A. chimpanzee B. mechanic C. chemistry D. earache 4. A. of B.funny C. wife D. bookshelf 5. A. conquer B.cook C. centimetre D. key II. Find one word which does not belong to each group. 1. A. like B. enjoy C. hate D. love 2. A. gardening B. skating C. running D. swimming 3. A. working B. sleeping C. relaxing D. resting 4. A. sunburn B. allergy C. sunlight D. flu 5. A. junk food B. orange juice C. milkshake D. lemonade 6. A. sick B. tired C. well D. sore 7. A. community B. compete C. complete D. compare 8. A. running B. running nose C. sore throat D. cold 9. A. donate B. provide C. collect D. money 10. A. clothes B. food C. provide D. money III.Put the following verbs into the correct tense. 1. I enjoy (fish) ………………. because it is relaxing. 2. She (love) ………………. swimming in the afternoon. 3. My friend hates (eat) ………………. out alone. 4. We suggest (watch) ………………. a horrible film. 5. What about (listen) ………………. to pop music. 6. Does she enjoy (do) ………………. gardening? 7. ………………. you (visit) ………………. your grandparents recently? 8. She (send) ………………. a letter to her pen-pal for 2 days. 9. They (write) ………………. this essay last week. 10. ………………. she (finish) ………………. school a month ago? IV. Put the correct form of the words in the following sentences. 1. English is an ………………. and important subject. (interest) 2. Ba has a large stamp ………………. (collect) 3. My mother works ………………. hours than yours. (many) 4. He drinks ………………. beer than me.(little) 5. Eating more vegetables and less meat will make you ………………. (health) 6. I don’t like this movie because it is so ………………. (bore) 7. He gets a cold, so he has a ………………. nose. (run) 8. There are ………………. symptoms when you have a cold. (differ) V Choose the best answer A, B, C or D. 1. My family has decided to use ….……. electricity by using more solar energy instead. A. more B. less C. much D. fewer 2. She studied very hard, ………………. she passed all the exams. A. so B. and C. because D. but 3. All of them enjoy ………………. to rock music. A. to listen B. listening C. listen D. to listening 4. My friend is interested in riding a horse. He rides a horse three ………………. a week. A. time B. a time C. times D. timings 5. The seafood she ate this morning makes her feel ………………. all over. A. well B. good C. itchy D. weak 6. You can help your young children learn better by ………………. them how to do homework after school. A. teaching B. doing C. offering D. helping 7. We ………………. to Ho Chi Minh three times. Last summer we ………………. there by plane. A. flew/ gone B. have flown/ have gone C. flew/ went D. have flown/went 8. When you have a flu, you may have a cough and a ………………. nose. A. run B. running C. runny D. flowing 9. It is interesting ………………. leaves from different countries. A. collect B. collecting C. to collect D. collected 10. I love playing volleyball, ………………. my father doesn’t. A. and B. so C. because D. but 11. Laughing is very good ………………. your health. A. for B. of C. at D. to 12. When you have a fever, you should drink more water, stay in bed and relax …………. A. much B. more C. most D. less 13. Volunteers always do general ……………. such as talking with the elderly, repairing houses, providing food and so on. A. matters B. labors C. jobs D. activities 14. Last year, our class came to the village and ………………. meals for the poor. A. cook B. offered C. do D. make 15. What has she ………………. for that orphanage? A. do B. did C. done D. doing