1. They advised him (not/ cross) not to cross_________ the street against the red lights. 2. He and his sister (not/ meet) _________ my friends since last Christmas. 3. She (work) ______ here since she left school? 4. Everyone (read) _______ this novel, let us (discuss) ______ it. 5. I (meet) _met_______ John before I (be) ________ a fortnight in Paris. 6. The children were frightened because the lights suddenly (go) ________ out and they (sit) ________ in the dark. 7. What tune (play)…………….when we (come)…………………… in? 8. She was badly hurt when her car hit another car. If she (wear) ________ her seat belt, she (not hurt) ________ so badly. 9. Although some groups of people (1. always live) _________ outdoors in tents, camping as we (2.know) _________ it today (3. begin) _________ to be popular about 50 years ago. The increase in the use of cars and improvements in camping equipment (4. allow) ________ more people to travel longer distances into the countryside and (5. stay) _________ there in greater comfort. Many campers like (6. be)………….themselves in quiet areas, so they take their tent and food and walk or cycle into the forests or the mountains. Others, (7. prefer) _________ to be near people, (8. drive) _________ to a public or privately-owned campsite which (9. have) ___________ up-to-date facilities like hot shower and swimming pools. Whether campers are separate in the mountain or on a busy site, they should remember to keep the area clean and tidy. In the forests, they must put out any fires and keep food hidden to avoid (10.attract) ………………… animals. giúp em ạ! em cảm ơn