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tranghuynh410
2 năm trước
Các bạn thiên tài vào đây giúp mình với!!! Cho tam giác abc,trung tuyến AN. G là trọng tâm tam giác abc.Qua G kẻ các đường thẳng song với AB và AC, cắt BC theo thứ tự tại E và F. a) Tính và so sánh các tỉ số BE/BN và CF/CN từ đó suy ra BE=CF b) C/m BE=DF=CF
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Chỉ e với mn II. PRACTISE Ex2. Fill in “have/has” (điền “have/has”). 1. Teddy ________ been a teacher since 2004. 2. I _______ been on holiday for six days. 3. They ______ never been to Madrid. 4. ________ you ever met anyone famous? 5. She _______ been married for two years. Ex 3. Write these sentences with Present perfect tense in negative, positive and question. (Dùng thì hiện tại hoàn thành để viết câu khắng định, phủ định và câu hỏi theo gợi ý) 1. (+) He has lived here for three years. (-)_____________________________________ (?) __________________________________ 2. (+) __________________________________ (-) We haven’t been here for two weeks. (?) __________________________________ 3.(+) __________________________________ (-)_____________________________________ (?) Have they missed the train? 4. (+) I have had breakfast this morning. (-)_____________________________________ (?)_____________________________________ 5. (+) __________________________________ (-)She hasn’t passed the exam. (?)_____________________________________ Ex 4. Make questions for the sentences below in the present perfect tense. (Hoàn thành những câu hỏi sau ở thì hiện tại hoàn thành) 1. He/ meet/ your family yet? ? 2. She/work/in this company for fifteen years? _________________________________________________________________? 3. How long/ she / live in London? ________________________________________? 4. How much coffee / you / drink today? ___________________________________? 5.What / you / do today? ________________________________________________? Ex5. Complete the sentences with the verbs in the present perfect. (chia động từ ở thì hiện tại hoàn thành và điền vào câu phù hợp) 1. The longest book I is The Lord of the Rings. 2. She the USA three times. Her aunt lives there. 3. I that film. Is it good? 4. I lots of photos with my camera. 5. They German before. This is their first year. 6. My team ten matches this year. Ex6. Put the verbs in brackets in the Present Perfect tense. (chia động từ ở thì hiện tại hoàn thành) 1. Peter and his brother (learn) English for three years. 2. Mr. Green (play) chess since eight o'clock. 3. It (not rain) since last week. 4. We (not see) our new teacher yet. 5. I (study) very hard for this examination. 6. My uncle (work) in this factory for ten years. 7. She (see) this film before. 8. The weather (be) quite good since Christmas. 9. I (have) this bike since I was a teenager, and I still use it. 10. He (play)______for the football club for several years, but it's time to leave it now. Ex7. Choose the best answer. 1. My sister is still studying.She her homework yet. A. haven’t finished B. not finished C. hasn’t finished D. has not finishived 2. Since moving to Alberta, I a lot about the oil industry. A. learned B. have learning C. have learned D. has learned 3. My father golf. A. never played B. have never played C. has never played D. has not playing 4. Our class 3 grammar quizzes so far this semester. A. has had B. have had C. had D. has having 5. I English for 10 years,but I still have a lot to learn. A. studied B. has studied C. have studied D. have studying Ex8.Complete the dialogue with the Present Perfect or the Simple Past of the verbs in brackets. (Hoàn thành bài hội thoại với thì hiện tại hoàn thành và quá khứ đơn) Minh: I (1. just, hear) that Hung is in Australia. Mai: Oh, (2. You/ not know) that? He (3. fly) there at the beginning of the month. Minh: (4. you/ hear) from him? Does he like the life there? Mai: Yes, I (5. get) a letter last week. He (6. tell) me about his study. But he (7. not say) whether he (8. like) the life or not. Perhaps it's too early to say. He (9. be) there for only three weeks. He (10. never/ be) to a foreign country before.

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