I was the edge of the canyon. A river was the bottom of the canyon.
| A．at；on | B．on；in | C．on；at | D．in；at |
-We could invite John and Barbara to the Friday night party.
-Yes, _______? I'll give them a call right now.
| A．why not | B．what for | C．why | D．what |
-How much difficulty did you have_______ this problem?
-_______. It's quite easy.
| A．to solve, Nothing | B．solving; None |
| C．to solve, None | D．solving; Nothing |
Yesterday morning I was just leaving_______ the telephone rang.
| A．when | B．while | C．because | D．since |
-When did your computer go wrong?
-Last night, while I_______ some music from a website.
| A．downloaded | B．am downloading |
| C．was downloading | D．have downloaded |
The girl devoted all her time she had_______ others.
| A．to help | B．helping | C．to helping | D．helped |