Mr. Wang is a nice teacher. He often helps his students with _______ physics after school.
| A．them | B．their | C．theirs | D．his |
We were swimming in the lake _______ suddenly the storm started.
| A．until | B．while | C．when | D．Before |
The price of petrol(汽油) is not _______ that of last year, so some more people are planning to buy cars.
| A．as expensive as | B．so cheap as |
| C．as low as | D．so high as |
Everybody should study hard. No one can _______ us _______ a good future.
| A．provide; for | B．provide; with |
| C．keep; / | D．protect; to have |
There’s water all over the kitchen. You’d better _______ right away.
| A．to mop up it | B．to mop it up |
| C．mop it up | D．mop up it |
I saw a number of pancakes in the plate, but now there is _______ left in it.
| A．none | B．something | C．nothing | D．no one |