Ten years ago the population of our village was that of theirs.
| A．as twice large as | B．twice as large as |
| C．twice as much as | D．as twice much as |
___ some teenagers don’t realize is ___ difficult life can be after they get addicted to drugs.
| A．What；how | B．What；what | C．That；how | D．That；what |
Among Asimov’s most famous works of science fiction, one ______he won an award, was the Foundation Trilogy.
| A．of whom | B．of which | C．for whom | D．for which |
When I approached to the subway entrance, an explosion occurred. This ___my first experience, I got into panic
| A．was | B．is | C．being | D．been |
Convenient ___private cars are for us, they may also cause traffic accidents and pollution.
| A．while | B．as | C．if | D．since |
You would not have made so silly mistakes , but it is a pity you _______ my advice.
| A．didn’t accept | B．hadn’t accepted | C．hasn’t accepted | D．wouldn’t have accepted |