It was playing computer games that cost the boy plenty of time he ____ doing his lessons.
| A．might have spent | B．ought to have spent | C．must have spent | D．could have spent |
No matter ______ the CRH accident in Wenzhou, it had and will have much warning significance.
| A．how the investigators said caused |
| B．what the investigators said caused |
| C．why the investigators said caused |
| D．the investigators said how caused |
I should apologize to you for failing to visit you last week, but I've been very busy_____ the past few months.
| A．since | B．before | C．among | D．over |
“As you need a day or two to ______ jetlag, you'll have a light schedule for today and tomorrow.” said my boss.
| A．go over | B．get over | C．turn over | D．take over |
Students are required to go out in couples, especially in the evenings, with friends ______ they get into trouble．
| A．even if | B．if only | C．in case | D．when |
--- How I regret making the stupid mistake!
--- Yes. Iyour doing it another way at that time, but in vain.
| A．have suggested | B．suggested |
| C．would suggest | D．had suggested |