____ he has made a decision, it is not easy for you to make him change his mind.
| A．Though | B．Unless | C．Once | D．Until |
The use of an alcohol breath test by the police greatly reduces the ____of drivers causing traffic accidents．
| A．possibility | B．pressure |
| C．preference | D．Production |
The couple give ________ attend their 50th wedding anniversary some gifts to share their happiness.
| A．whoever | B．whomever | C．whom | D．Who |
So touching_____ that I couldn’t hold my tears back when I heard it for the first time
| A．the song sounds | B．had the song sounded |
| C．the song sounded | D．did the song sound |
Frequent smoggy weather has set the alarm ringing; by no means can we develop economy _____ the environment.
| A．under the name of | B．for the sake of |
| C．at the cost of | D．in the light of |
The English play _____ my students acted at the New Year’s party was a great success.
| A．for which | B．in which |
| C．at which | D．on which |