基坑(槽)的土方开挖时,一般应采用的开挖原则是()。
A.分段开挖,先挖后撑
B.分层开挖,先挖后撑
C.分段开挖,先撑后挖
D.分层开挖,先撑后挖
参考答案:C
用所给词的适当形式填空。
1. ________ (he) favorite food is hot dogs.
2. Would you like ________ (eat) salad?
3. Don't let the boy ________ (draw) pictures on the wall.
4. The man looks very _______ (friend) .
5. One of the _______ (run) wears black shoes.
6. This is the ________ (begin) of your English study.
7. Mary likes ________ (play) chess very much.
8. ________ (not take) the book out of the library, please.
9. What about ________ (go) for a walk with me?
10. He really enjoys ________ (read) very much.
透平在开车过程中()。
A.必须暖机
B.不必暖机
C.开盘车
D.停油泵