18. ______ a little more time to think, he might have acted more sensibly.

A. If he took　 　B. If he has taken 　C. had he taken 　D. Should he take

17. ______ notebook and report that I promised you last week.

A. Here is the 　B. Here are the 　C. Is here the 　D. Are here the

16. A sneeze cannot be performed voluntarily, ______ be easily suppressed.

A. nor it can 　B. nor can it 　C. it cannot 　　D. and cannot it

15. So fast ______ that it is difficult for us to imagine its speed.

A. light travel 　B. travels the light 　C. do light travel 　D. does light travel

14. ______, I must do another experiment.

A. Be it ever so late 　B. It is ever so late　 C. It be ever so late 　D. So late it be ever

13. Her answer is not acceptable, and ______.

A. neither am I 　B. either is mine 　C. neither is mine 　D. mine is neither

12. ______ is it only the ignorant and ill-educated person who has such faith in the bottle of medicine.

A. Either 　　B. Often 　　C. Nor　　 　D. Usually

11. ______ do we go for picnics.

A. Certainly 　B. Sometimes 　C. Seldom 　　D. Once

10. ______ that they may eventually reduce the amount of labor needed on construction sites by 90 percent.

A. Such construction robots are clever　　 B. So clever the construction robots are C. So clever are the construction robots　　 D. Such clever construction robots are

9. On no account ______ to anyone.

A. my name must be mentioned 　　　B. must my name mention

C. must my name be mentioned　　 　D. my name must mention