Having lived in China for 8 years, Helen has a good ______ of both English and Chinese．
| A．program | B．guidance | C．command | D．ability |
一What did he want to know，John?
一that we could finish our work．
| A．What it was | B．When was it | C．When it was | D．What was it |
Although everything seems to have been taken into consideration，accident can happen when the astronauts walk in space．
| A．不填；the | B．an；the | C．the；the | D．an；不填 |
She wasn’t a much older tennis player but he had the great ______ of experience about games.
| A．interest | B．advantage | C．benefit | D．profit |
I think you should complain----______, of course, you are happy with the way things are.
| A．if | B．unless | C．as | D．because |
Only when Tom fully recovered ______ back to work.
| A．did he go | B．he went | C．had he gone | D．he had gone |