Task 1. Choose the necessary word: 1. My sister ___ very beautiful. She’s arriving today. (who/that) 2. He’s bought the toy ___ she was looking for today. (who/that) 3. Jerry’s father has been building his country house ___ ten years. (for/since) 4. Alex wanted a car ___ her last birthday. (for/since) 5. The textbook ___ by Andy. (wrote/was written) 6. Five people ___ in a plane crash. (have killed/have been killed) 7. A famous designer ___ the bridge. (was built/built) 8. Mikki ___ play the piano very well. (can/should/must) 9. ___ the help you with this task? (Could/Must/May) 10. It’s raining. You ___ take an umbrella. (can’t/don’t have to/should)

1. My sister, who is very beautiful, is arriving today. Придаточное относится к человеку, поэтому используется who.
2. He’s bought the toy that she was looking for today. Для предмета используется that.
3. Jerry’s father has been building his country house for ten years. For употребляется с продолжительностью действия.
4. Alex wanted a car since her last birthday. Since употребляется с начальным моментом времени.
5. The textbook was written by Andy. Используется страдательный залог.
6. Five people have been killed in a plane crash. Люди являются объектом действия.
7. A famous designer built the bridge. Действующее лицо — дизайнер.
8. Mikki can play the piano very well. Can обозначает умение.
9. Could the help you with this task? Вероятно, в условии имеется в виду: Could you help me with this task? — вежливая просьба.
10. It’s raining. You should take an umbrella. Should выражает совет.

Ответ: 1 — who; 2 — that; 3 — for; 4 — since; 5 — was written; 6 — have been killed; 7 — built; 8 — can; 9 — Could; 10 — should.