If you go for a long ride in a friend's car, it's the custom to offer to __________ some of the expenses.
| A．pay |
| B．pay off |
| C．pay for |
| D．pay back |
_______ you have got used to it , you’ll like it .
| A．While | B．On the condition | C．Once | D．Unless |
We’ll carry the work through , cost _______ it may .
| A．what | B．when | C．where | D．how |
Persist to the end , _______ you are the only one left.
| A．even if /though | B．but | C．however | D．in spite of |
He always talks _______ he had been to outer space.
| A．like | B．as if /though | C．because of | D．as |
You’d better come back earlier _______ it is getting colder.
| A．as | B．and | C．but | D．or |