We should keep in mind that the earth is our only home and only by saving the environment________ourselves.
| A．we can save | B．can we save |
| C．we must save | D．must we save |
We should not _______ small mistakes, or they might lead to big accidents.
| A．hurt | B．ignore |
| C．recover | D．dislike |
—Her father is very rich.
—_______ She wouldn’t accept his help even if it were offered.
| A．What for? | B．So what? |
| C．No doubt. | D．No wonder. |
Life is like a long race _____ we compete with others to go beyond ourselves.
| A．why | B．what | C．that | D．where |
If you _____ smoke, please go outside.
| A．can | B．should | C．must | D．may |
-----Is there any possibility ______ you could pick me up at the airport?
----- No problem.
| A．when | B．that | C．whether | D．what |