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cho tam giác ABC cân tại A đường cao thuộc cạnh bên bằng H góc đáy bằng alpha chứng minh rằng: Sabc=H^2 phần 4 nhân sin alpha nhân cos alpha
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X. Fill in each blank with a proper expression of quantity. Use of where necessary. 1. I feel lonely here because I have _______________________ friends in this city. 2. These books are all Jane’s. _______________________ them belong to me. 3. Not all the people I work with are very friendly. ___________________ them are unfriendly at all. 4. Are those people English? No, just _______________________ them. 5. _______________________ schools open in September. 6. Let’s go and have a drink. We’ve got _______________________ time before the train leaves. 7. Have you got ______________ money? ~ Yes, but not _______________________. 8. Hurry or we’ll be late. We have very _______________________ time. 9. I have done _______________________ the exercises of grammar in this book, so I’m going to buy another book. 10. We all got wet in the rain because _______________________ us had an umbrella. 11. We’ll have to work quickly because I haven’t got _______________________ time. 12. I do not know __________________ about biology, but I have ___________________ knowledge about genetics. 13. The librarian says that you may borrow as _______________________ books as you want to. 14. The boys are making too _______________________ noise. 15. I watched _______________________ the film but not all of it. 16. I’m very poor. I have _______________________ money. But my brother is richer than I. He has _______________________ money in the bank. 17. Before mixing the cake, weight _______________________ ingredient precisely. 18. When my rich uncle died, he left _______________________ his fortune to his cat. He hadn’t left _______________________ it to us. 19. How ______________________ languages can you speak? And how _______________________ time do you spend on learning English? 20. When my rich uncle died, he left _______________________ his fortune to his cat and the other half to a distant cousin! We had never expected to receive _______________________ it, but we were disap¬pointed that he hadn’t left _______________________ it to us.

1Ann is very tired . she _____ tennis for three hours A:is playing B:will play C:plays D:has been playing 2 he works in a bank, but he ______ it very much A:doesn't enjoy B:haven't enjoy C:đin't enjoy D:hadn't enjoy 3 I ____ well lattely.Mabe I should go to the doctor A: didn't feel B:won't feel C:haven't been fee;ing D:am not feeling 4 I _____ my homework for two hours,but I ____ yet A:have done-haven't finished B:is doing-isn't finishing C:will dp-will not finish D:have been doing-haven't finished 5let's take our travel chess set in case wwe _____ bored on the train A:Get B:are getting C:got D:have got 6 we ____ get in touch with our customers by post A:recently B:hardly C:lately D:latterly 7 We have been married ______ A:over twenty years B:over twenty years ago C:for over twenty years D:since over twenty years 8 melanie ______- her hand. It's bleeding heavily A:has cut B:is cutting C:cut D:cuts 9" when will Mary be able to leave hosptal?" - "Don't be so impatien. we cannot realease her before we ________ the last test A:have complete B:will have completed C:will complete D:completed 10 The Amazon river____ into the Atlantic Ocean A:flows B:has flowed C:is flowing D:will flow 11 My parents live in London. They _______ there all their lives A:are living B:had lived C:have lived D:will live 12 where have you been? I ____ for you the last half hour A:am looking B:have been looking C:will be looking D:look 13 My brother is an actor. He ______ in several movies A:appeared B:had appeared C:has appeared D:appears 14 Please don't bother hom now. he ________ A:is working B:has been working C:had been working D:was working 15 I _______ an interesting book at the moment. I will lend it to you when I ____ it A:am reading - have finished B:read - am finishing C:have read - am finishing D:read -will finish 16 Ha never ______ fishing in the winner but she always ___-it in the summer A:goes-does B:has gone - done C:go - do D: was gone - done 17 we can win only if we remain united, so we must suppor them the moment they_____ on strike A:will have gone B:will go C:go D:went 18 I am sr . i ______ that fellow's name already A:forgot B:have forgotten C:have been forgetting D:forget 19It usually ______ very much in that part of the United States A:is rainning B:rained C:rains D:have rained 20 look! A man _____ after the train. he wants to catch it A:runs B:have been running C:will run D:is running

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