专项练习
1. Economics, several courses of which I have taken thus far, ______ to be difficult but useful for almost all students.
A. prove B. proves C. have been proved D. are proved
2. A thousand miles no longer _______ much to us today, for modern jets can easily get us to a great distance within a matter of a few hours.
A. meant B. means C. mean D. will mean
3. The secretary and treasurer of our company ______ the meeting.
A. were to attend B. are to attend C. is attend D. is to attend
4. Cattle ______ to graze on the village common.
A. are allowed B. is allowed C. allows D. allow
5. Mathematics as well as other subjects ____ a science.
A. was B. is C. are D. belong to
6. Either of these young ladies ____ perfectly qualified to teach Greek, Latin and French.
A. were B. are C. is D. have been
7. Large quantities of water ______ cooling purposes.
A. are needed for B. is needed to C. are needed to D. is needed for
8. Copper as well as most metals____.
A. is a good conductor B. is a good insulator
C. are good conductors D. are good insulators
9. There used to be some trees by the lake, ____ ？
A. was there B. were there C. weren't there D. wasn't there
10. Cattle____ to graze on the village common.
A. are allowed B. is allowed C. allows D. allow
