Scientists are convinced--- the positive effect of laughter___ physical and mental health．
| A．of；at | B．by；in | C．of；on | D．on：at |
There was a traffic jam; otherwise I ____ here on time.
| A．would be | B．had been | C．should be | D．would have been |
---Laura can’t come for dinner. She’s leaving for Beijing tonight.
--- _____. I hope I can talk to her soon.
| A．What a shame | B．Never mind | C．Yes, she should | D．With pleasure |
It’s important to write these goals down______ merely think about them.
| A．more than | B．rather than | C．other than | D．less than |
Regulations _____ that students attend at least 90% of the lectures.
| A．demand | B．ask | C．require | D．request |
It’s ten years since the scientist ___on his life’s work of discovering the valuable chemical.
| A．made for | B．set out | C．took off | D．turned up |