It was not until he lost all of his friends _________ he realized the importance of friends.
| A．when | B．who |
| C．which | D．That |
We live in ____ neighbourhood of the school and go to school on ____ foot.
| A．the; / | B．the; the | C．a; / | D．a; the |
There are lots of plastic bags ____ in the river, ____ it very dirty.
| A．floating; making | B．to float; made |
| C．being floated; made | D．floated; making |
--- Would you mind if I used your bike?
--- ____.
| A．Of course | B．Go ahead | C．Good luck | D．Good idea |
The president spoke at the business meeting for nearly an hour without ____ his notes.
| A．bringing up | B．looking for | C．referring to | D．trying on |
David worked hard at his lessons ____ he gained high grades in the exams.
| A．so that | B．in order to | C．though | D．because |