He is only too ready to help others, seldom, ____, refusing them when they turn to him.
| A．if never | B．if ever | C．if not | D．if any |
Try ____ she might, Sue couldn’t get the door open.
| A．if | B．when | C．since |
D．as |
More than one company ___ the new design to market only to see it quickly denied by those who couldn’t wear them.
| A．has taken | B．has been taken | C．have taken | D．have been taken |
During our stay in London, the guide book ___ a great help. We all had a wonderful time.
A. behaved B conducted C. served D. proved
Her behavior is __________.
| A．worthy praise | B．worthy to be praised |
| C．worth to be praised | D．worth being praised |
—The room is so dirty, _____ we clean it?
—Of course.
| A．will | B．shall | C．would | D．do |