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1. They are going to live with Sina in London.
2. If he were here now, he would help us do homework.
3. The girl has been seen in the park by them.
4. Because Tom is not tall enough, he can't reach the shelf.
Nếu đề là câu điều kiện :
3. If the girl weren't in the park, they wouldn't see her. ( câu này nếu đề là câu bị động sẽ hợp lí hơn bạn nhé.)
4. If Tome were tall enough, he could reach the shelf.