Nhân giống thuần chủng thường được ứng dụng trong các trường hợp nào???

1. She ( eat ) ______________ chicken for dinner several times last week.

2. Last night Becky ( cook ) __________ a spicy chicken and rice dish for her friends.
3. It ( be ) ______________ delicious, and they ( love ) ______________ it.
4. While she was cooking dinner, she ( drop ) ______________ a pan of hot oil on the floor, butfortunately she ( be) ______________ okay. It ( burn, not ) ______ her.
5. Yesterday morning I ( get)______________ up at 6:30.
6. We needed some money so we ( sell)______________ our car.

7. You ( go)______________ out last night ?
8. This house ( cost) ______________ 35,000 pounds in 1980.
9. While Tom ( play)______________ tennis. Ann ( take)__________ a shower.
10. When they ( work) ______________ in the garden, the phone ( ring)_______ .
11. After they ( have)______________ their breakfast, they ( go)______________ shoppingyesterday.
12. Somebody (steal) ______my sunglasses at the swimming pool last week.
13. (she wear) ______________ the nice jacket when you saw her?
14. Where (be) ______________you yesterday?

15. She (get)______________ to her feet, (slip)______________ into her coat, and (go)______________ to the door. When she (open)______________it, she (look)______________ back at her mother.

16. What tune (play)______________ when we (come)______________in?
17. She told me that her family (live)______________ in that town long.
18. Within a week she (know) __________ the fearful mistake she (make)_______.

19. I (sit)______________ down for a rest while the shoes (repair)______________.

20. Before I (go) ______to London, I (not / enjoy) _______learning English.

21. While Mary was cleaning the apartment, her husband ( watch)____TV.

22. I've been in this city for a long time. I (come) ___ here sixteen years ago.

23. They(live)____in Beijing for three years when he lost his job.
24. When we met, you(work) ____ at that company for six months.
25. The phone ( ring) ____ constantly since Jack announced his candidacy for president this morning.

26. The earth ( depend) ______on the sun for its heat and light.
27.We (sleep) ____ for 12 hours when he woke us up.
28. They (wait) ____ at the station for 90 minutes when the train finally arrived.
29. We (look for) ____ her ring for two hours and then we found it in the bathroom.
30. I (not/walk) ____ for a long time, when it suddenly began to rain

31. The last time we went to Ho Chi Minh City was in 2009.→We haven’t.................................................................................................................

32. I started playing tennis 2 years ago.→I have.........................................................................................................................

.33. I last visited Tom 3 months ago.→I haven’t......................................................................................................................

→It’s ...............................................................................................................................
→The last .......................................................................................................................
34. I started doing homework two hours ago.→I have .........................................................................................................................
35. I started working in this company when I came back from Paris.→ I have .........................................................................................................................

36.I started writing this novel 3 months ago. (for)→Ihave.........................................................................................................................
37.She has been playing the piano since she came back from school. (when)→Shebegan..........................................................................................................
38. We bought our house 10 years ago.→ Our house...................................................................................................................

39. They have considered me as their great friend.→I............................................................................................................................

40. My sister began to learn English when she was six years old.→My sister has.......................................................................................................

tại sao kích thước cơ quan sinh dưỡng và sinh sản của cây đa bội thể lại lớn hơn cây bình thường