一.用括号中所给单词的适当形式填空,使句子完整,通顺.一．用括号中所给单词的适当形式填空，使句子完整、

一．用括号中所给单词的适当形式填空，使句子完整、通顺。
1. He preferred _staying________ (stay) at home to __going______ (go) out.
2. I prefer __to walk____ (walk) rather than __travel___ (travel) by car.
3. The old house was dark and __lifeless_______ (life). It looked scary.
4. In winter, animals like staying together for ___warmth____ (warm). 
5. Stop _pilluting__(pollute) the river, or we won’t have clean water to drink.
6. These years _floods_(flood) often take place because of the greenhouse effect.
7. If we continue damaging the earth, the environment will become even __worse__ (bad).
8. The _cutting_ down of trees is making the greenhouse effect worse. (cut)
9. He got up very early this morning and __caught__ the first bus.  (catch)
10. It lets sunlight in and keeps much of the __warmth_ from getting out.  (warm )
11. Because of _pollution________, too much heat is kept in Earth. (pollute)

1. to stay going
2. to walk traveling
3. lifeless
4. warming
5. polluting
6. floods
7. worse
8. cutting
9. caught
10. warmth
11. pollution