It was __________ computer games that cost the young man a lot of precious time that he ought __________ on his lessons．
| A．to play, to be spending | B．playing, to spend |
| C．played, to have spent | D．playing, to have spent |
Thank you for_______ my trouble.
| A．talking | B．going | C．sharing | D．getting |
It is worth considering what makes “convenience” foods so popular, and ____ better ones of your own.
| A．introduces | B．to introduce |
| C．introducing | D．introduced |
I’m sorry you’ve been waiting so long, but it’ll still be some time ____ Brian get back.
| A．before | B．since | C．till | D．after |
If you really have to leave during the meeting, you'd better leavethe back door.
| A． | for | B． | by | C． | across | D． | out |
I feel greatly honoredinto their society.
| A． | to welcome | B． | welcoming |
| C． | to be welcomed | D． | welcomed |