29．The young man，who by then admission to university，decided to do some part-time jobs to gain more practical experience．
| A．gained | B．was gaining | C．has gained | D．had gained |
The doctor recommended that you ________ swim after eating a large meal.
| A．wouldn't | B．couldn't | C．needn't | D．shouldn't |
Jack is a great talker.It's high time that he ________ something instead of just talking.(2012·辽宁)
| A．will do | B．has done | C．do | D．did |
—Where are the children？The dinner's going to be completely ruined.
—I wish they ________ always late.(2011·北京)
| A．weren't | B．hadn't been |
| C．wouldn't be | D．wouldn't have been |
________ the problem, he wouldn't have committed those mistakes.
| A．If he understood | B．Had he understood |
| C．When he had understood | D．If he would understood |
________ I be free tomorrow, I would go with you.
| A．Could | B．Should | C．Might | D．Must |