Ở đậu Hà Lan, alen quy định thân cao trội hoàn toàn so với alen quy định thân thấp. Một cây thân cao thuộc loài này (kí hiệu là cây M) chưa biết kiểu gen. Có bao nhiêu cách sau đây giúp xác định chính xác kiểu gen của cây M? (I). Cho cây M tự thụ phấn. (II). Cho cây M giao phấn với cây thân thấp. (III). Cho cây M giao phấn với cây thân cao thuần chủng. (IV). Cho cây M giao phấn với cây thân cao có kiểu gen dị hợp. A: 1 B: 4 C: 2 D: 3.

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I. Complete the sentences using the past simple form of the verbs: 1. Yesterday, I (go)______ to the restaurant with a client. 2. We (drive) ______ around the parking lot for 20 mins to find a parking space. 3. When we (arrive) ______ at the restaurant, the place (be) ______ full. 4. The waitress (ask) ______ us if we (have) ______reservations. 5. I (say) ______, "No, my secretary forgets to make them." 6. The waitress (tell)______ us to come back in two hours. 7. My client and I slowly (walk) ______ back to the car. 8. Then we (see) ______ a small grocery store. 9. We (stop) ______in the grocery store and (buy) ______ some sandwiches. 10. That (be) ______ better than waiting for two hours. 11. I (not go) ______ to school last Sunday. 12. She (get) ______ married last year? 13. What you (do) ______ last night? - I (do) ______ my homework. 14. I (love) ______ him but no more. 15. Yesterday, I (get) ______ up at 6 and (have) ______ breakfast at 6.30. 16. I (not stay) _____ at home all weekend. 17. Angela (go) ______ to the cinema last night. 18. My friends (have)______ a great time in Nha Trang last year. 19. My vacation in Hue (be)______ wonderful. 20. Last summer, you (visit) _____ Ngoc Son Temple in Ha Noi? 21. your parents ( be) ____ very tired after the trip? 22. I (buy)_______ a lot of gifts for my little sister. 23. Where Lan and Mai (see) _______ sharks, dolphins and turtles? 24. Who Trung (eat)_____ chicken and rice for dinner with? 25. They (not talk) ____ about their holiday in Hoi An. 26. Phuong (return) _____ to Hanoi yesterday? 27. We (think)_____ the food was delicious. 28. Yesterday, I (go)______ to the restaurant with a client. 29. There (be) ______ some men in the hall. 30. Mum (not spend) ___________ any money on herself. 31. Yesterday, I (go)______ to the restaurant with a client. 32. (Be) ______ there any sugar in the pot? 33. We both (sleep) ___________ badly that night. 34. He (lay) ___________ his hand on my shoulder. 35. Then we (see) ______ a small grocery store. 36. Who (buy) ______ you this bag? 37. I (not go) ______ to school last Sunday. 38. We (stop) ______ in the grocery store and (buy) ______ some sandwiches. 39. Why your brother (be) ______ so late? 40. Yesterday, I (get) ______ up at 6 and (have) ______ breakfast at 6.30.