—May I speak to your manager Mr.Williams at five o’clock tonight?
—I’m sorry. Mr. Williams ________ to a conference long before then.
| A.will have gone | B.had gone | C.would have gone | D.has gone | 
Tom told us all that he said so at the meeting was really true.
| A.that | B.all | C.what | D.which | 
This ischallenging job I mentioned to you the other day. Have you had anyone inmind for it now?
| A.a, the | B.the;/ | C.the, the | D.a:/ | 
In such a background, his white hair was particularlyhis dark skin.
| A.in relation to | B.in need of | C.in contrast to | D.in favor of | 
The black baby boy is at the stagehe can only say a few simple words but not yet full sentences.
| A.when | B.where | C.which | D.why | 
Up to now, no one has come up with a(n)explanation of why dinosaurs died out, and it remains a mystery.
| A.astonishing | B.amusing | C.convincing | D.puzzling |