Many countries are now setting up national parks _ animals and plants can be protected.
| A．which | B．whose | C．when | D．where |
He seems to be doing nothing, but _____ he is just waiting for his chance.
| A．actually | B．gradually |
| C．frequently | D．certainly |
The boss requested that he _____ there to work.
| A．was sent | B．be sent |
| C．should send | D．would be sent |
You must ______ your papers before you hand them in.
| A．go down | B．go across |
| C．go out | D．go through |
Did you have any difficulty _____ his house?
| A．on finding | B．to finding |
| C．for finding | D．in finding |
He failed in the exam not only his laziness but also he didn’t listen to the teacher.
| A．because; for | B．because of; because |
| C．as; for | D．for; since |