The Russian rocket designer has died. For many years, he ______ as an important assistant to the father of Soviet space program.
| A．serves | B．was serving | C．served | D．has served |
__________ has been announced, we shall have our final exam next month.
| A．As | B．It | C．That | D．What |
I haven't my photograph album _____________, but I'll show it to you later．
| A．at hand | B．at work | C．at ease | D．at length |
My headache _________ me．I thought it was going away, but it's getting worse and worse．
| A．killed | B．kills | C．is killing | D．was killing |
What I need is ___________ book that contains _____ ABC of English grammar．
| A．a; the | B．the; 不填 | C．the; an | D．a; 不填 |
—Did he come back late last night?
—No．It was not yet eight o'clock _____________ he arrived home．
| A．before | B．that | C．until | D．when |