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Jnhi_2000
2 năm trước
Cho hình thang ABCD có A = D = 90 và hai đường chéo vuông góc với nhau tại O a) c/m AD= √AB.CD b) cho AB =9 , CD =16 .Tính S ABCD
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Bài 1: Bài tập về các thì 1. I (learn) English for seven years now. 2. But last year I (not/ work) hard enough for English, that's why my marks (not/ be) really that good then. 3. As I (pass/ want) my English exam successfully next year, I (study) harder this term. 4. During my last summer holidays, my parents (send) me on a language course to London. 5. It (be) great and I (think) I (learn) a lot. 6. Before I (go) to London, I (not/ enjoy) learning English. 7. But while I (do) the language course, I (meet) lots of young people from all over the world. 8. There I (notice) how important it (be) to speak foreign languages nowadays. 9. Now I (have) much more fun learning English than I (have) before the course. 10. At the moment I (revise) English grammar. 11. And I (begin/ already) to read the texts in my English textbooks again. 12. I (think) I (do) one unit every week. 13. My exam (be) on 15 May, so there (not/ be) any time to be lost. 14. If I (pass) my exams successfully, I (start) an apprenticeship in September. 15. And after my apprenticeship, maybe I (go) back to London to work there for a while. 16. As you (see/ can), I (become) a real London fan already.

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