-___________ to their own
work，most of the parents spend little time with their
children.
| A．Devoting | B．To be devoted | C．Having devoted | D．Devoted |
When you read the book, you' d better make a mark _____ you have any questions.
| A．at which | B．at where | C．the place | D．where |
We'd better hurry ______ it is getting dark.
| A．and | B．but | C．as | D．unless |
I didn' t manage to do it _____ you had explained how.
| A．until | B．unless | C．when | D．before |
_____ he comes, we won't be able to go.
| A．Without | B．Unless | C．Except | D．Even |
I hurried _____ I wouldn't be late for class.
| A．since | B．so that | C．as if | D．unless |