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nguyenvietbinhduong8a7
2 năm trước
1 tia sáng đi từ môi trường trong suốt có chiết suất n đến mặt phân cách giua 2 môi trường đó với không khí với góc tới 30 độ.Khi đó tia khúc xạ hợp với mặt phân cách góc 45 độ a)Tính n b)Nếu góc tới là 60 độ thì góc khúc xạ là bao nhiêu
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1 / 2 Exercise 4: Choose the best answer to complete these following sentences. 1. If you don’t feel well, you_____________ better take a rest. A. are B. would C. had D. have 2. What would you have done if you _____________ a lot of money? A. had B. had had C. have had D. have 3. The movie was sad and she wept. If it_____________ sad, she_____________. A. hadn’t been/ wouldn’t have wept B. wasn’t/ wouldn’t weep C. wasn’t/ would weep D. had been/ would have wept 4. I’ll be very disappointed if you _____________ the exam. A. don’t pass B. won’t pass C. aren’t passing D. wouldn’t pass 5. If he _____________ harder, the results would be better. A. has worked B. works C. will work D. worked 6. If I had had free time, I _____________ shopping. A. would have gone B. can go C. will go D. will have gone 7. _____________ if you take the map with you. A. You will get lost B. You won’t get lost C. You get lost D. You got lost 8. If you had come to the party, you _____________ her. A. would meet B. had met C. would have met D. met 9. I’m not tired enough to go to bed yet. I wouldn’t sleep if I _____________ to bed now. A. go B. went C. had gone D. would go 10. If I were you, I _____________ that shirt. It’s much too expensive. A. won’t buy B. don’t buy C. am not going to buy D. wouldn’t buy 11. I decided to stay at home last night. I would have gone out if I _____________ so tired . A. wasn’t B. weren’t C. wouldn’t have been D. hadn’t been 12. "Did he lose?" "Yes, but if he had tried harder, he_____________ won." A. might B. might have C. might of D. might has 13. What will I do if no one _____________ me at the airport? A. meet B. will meet C. meets D. met 14. Jean gets very agitated if her daughter _____________ her once a week. A. doesn't ring B. didn't ring C. not ring D. don't ring 15. ______________________________. A. People will die if there is no water and air. B. If there were no water and air, people would die. C. People will not die if there is no water and air. D. If there were no water and air, people would not die. 16. If you_____________ that plane, you _____________ dead now. A. had caught / would have been B. caught / would be C. had caught / would be D. catch / will be 17. I would have said "good bye" to your brother if he_____________ there. A. could be B. had been C. will be D. will have been 18. If you_____________ what Nam is doing, you _____________ very surprised . A. had known / would be B. knew / would be C. knew / would have been D. knew / will be 19. I _____________ very happy if there _____________ a good film on channel 9 last night. A. would be / had been B. would have been / would be C. would have been / had been D. had been / had been 20. If you see Tom, _____________ you mind _____________ him to get in touch with me? A. will / reminding B. will / to remind C. would / reminding D. would / to remind

Bạn nào giúp mình với ạ I. Choose one word whose underlined part is pronounced differently from the others by circling A, B, C or D. 1. A. action B. national C. partial D. question 2. A. tidal B. sight C. describe D. cinema 3. A. connect B. comfort C. computer D. contest 4. A. cough B. though C. rough D. tough 5. A. pleased B. erased C. increased D. amused II. Choose one word whose stress pattern is different from the others by circling A, B, C or D. 1. A. medical B. restaurant C. remember D. government 2. A. household B. homework C. garbage D. throughout 3. A. electrical B. interesting C. necessary D. beautifully 4. A. celebrate B. consider C. expression D. criteria 5. A. partner B. between C. visit D. program III. Choose the best answer to complete the sentences by circling A, B, C or D. 1. - Mary: “Is 11 o’clock alright?” - Tom: “______.” A. Yes, that’s fine B. No, I don’t want to go C. Wait a minute D. Sounds interesting 2. Typhoons, floods or droughts can easily ______ a harvest. A. finish B. destroy C. provide D. defeat 3. You should pay ______ to what the instruction is saying. A. attendance B. intention C. convention D. attention 4. My friends usually enjoy my ______ of humor. A. sense B. kind C. means D. form 5. - Mother: “Could you do me a favor?” - Kate: “______.” A. No, thanks. I’m fine B. Yes, that’s kind of you C. Yes, sure D. Yes, thank you 6. Practising ______ English anywhere you can is a way to better your speaking skill. A. speak B. speaking C. to speak D. for speaking 7. Soak some old newspapers in a ______ of water overnight. A. pair B. bunch C. bucket D. tube 8. Mrs. Thanh: “______ you give the book to me, please?” - Mai: “Of course.” . A. Will B. Shall C. Do D. Should 9. The winners are the first ones ______ a fire. A. make B. makes C. making D. to make 10. Children may drink or eat chemicals and drugs ______ they look like soft drinks and candy. A. until B. because C. although D. so that

IV.Chia động từ trong ngoặc. 1. I (be) Lan . ….…………………………………… 2. What you (do) in your free time? ………………………………………. 3. Mai (go) to school every morning. ……………………………………… 4. We (do) our tests now. ……………………………………… 5. He wants (go) camping. ……………………………………… VII. Reas then answer. My uncle is an engineer. His name is Hung. He is going on vacation this summer. First, he is going to visit Ha Long Bay. He is going to stay in a small hotel near the bay for two days. Then he is going to visit Da Lat for three days. Finally, he is going to visit some friends in Ho Chi Minh City . He is going to stay there for one day . He is going to walk along Saigon River. He is going to fly home. 1. How many cities is your uncle going to visit?  ………………………………………………….. 2. Is he going to visit Da Lat first?  ………………………………………………….. 3. How long is he going to stay in Ha Long Bay?  ………………………………………………….. 4. What is he going to do in Ho Chi Minh city?  …………………………………………………..

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