28. If you want to do the experiment again, you had better be more careful_______ you made a mistake.

A. when　　 B. why　　　 C. where　　　　 D. that

27.------ He should have been warned of the danger.

------_________, but he wouldn’t listen to me.

A. So he was　 B. So was he 　　　　 C. So should he 　　 D. So he should

26. ______ a mobile phone can you ring _____ you want to talk with anywhere.

A. Using, whoever　　　　　　　　 B. Only on, whomever　

C. By , whomever　　　　　　　　 D. Not only with, whoever

25.We don’t doubt ____ he’ll give us much help. _____ we doubt is _____ he’ll come on time

A. whether, That, when　　　　 　 　　　B. that, What, whether

C. whether, What, whether　　　　　 　　 D. that, Why, whether

24.　 ______ with great pressure in the job market, university graduates start to make use of blogs to attract publicity.

A. To face　　　　　　 　 B. Facing　　　　　　 C. To have faced　　　　　 　　 D. Faced

23. Our school forbids_____ ,that is to say, we are not allowed ____ at school.

A . to smoke, to smoke　　　　　　　 　 　　　　B. students’ smoking, smoking

C. students’ to smoke, smoking　 　　　 D. students’ smoking, to smoke

22. Smoking too much may 　　　　lung cancer and cause other diseases.

A.devote to　　　　　 B.attend to　　　　　　　　　　tribute to　　　　　　　 　e to

21. In 1942,Columbus and his crew arrived ____was so-called the New World by the westerners.

　　 A .what　　　　 　B .in what　　　　　 C. where　　　　　 D. in which