The boy _____ he took notes.
| A．listened with attention | B．listening attentively while |
| C．listened attentively before | D．listening with attention |
It is much better to ask someone for advice rather than something.
| A．risk doing |
| B．risk to do |
| C．to risk doing |
| D．to risk to do |
The professor can hardly find sufficient grounds his argument in favor of the theory.
| A．which to base on |
| B．on which he bases |
| C．to base on which |
| D．which to be based |
—Sorry，my dog frightened your daughter.
—Forget it！________.
| A．She deserved it |
| B．Every dog has its day |
| C．Bad luck comes three |
| D．Animals will be animals |
The teacher stressed again that the students should not________any important details while retelling the story.
| A．bring out |
| B．let out |
| C．leave out |
| D．make out |
I will put the book________you placed it and make a mark at the place________I put it.
| A．where；at which |
| B．at which；at which |
| C．where；which |
| D．at which；where |