d 如将a项中was, since改成is, since是正确的；即从句中谓语先发生。如用b项，是强调句，而强调句前后两个谓语动词在时间

上必须一致（a）；被强调部分能还回原句中（b），即因为句中was declared是过去时, b项中is改成was；因为句中was declared是非延续性动词，在years后加上ago将一段时间变成一点就是正确的。c 项前后时间不一致。

5. the professor said he could talk on _____ interested the audience.

a. any topic

b. which topic

c. whichever topic

d. the topic he thought it

c whichever已失去疑问含义，等于 anything that，表示强调；

而 which topic中 which保留疑问含义，译成哪一个题目，不符合句义。而a和d中缺少连词。

6.under no circumstance _____ to tell lies to parents.

a. children are allowed

b. are children allowed

c. children will allow

d. will children allow

b.含有否定意义的副词及介词短语放在句首时，句子中主语和谓语用部分倒装。

7.modern science and technology has _____ communication between people far apart.

a. made convenient

b. made it convenient

c. made it convenient for

d. made it convenient to

a 题目中has made是谓语，communication between people far apart短语是宾语，convenient是宾语的补语，被前置。如用b

项,it是形式宾语代替不定式或从句。

8.i heard that you really had a wonderful time at johns birthday party, _____?

a. didnt i

b. didnt you

c. hadnt you

d. will you

b含宾语从句和定语从句的主从复合句，反意疑问句随主句变；但是在含有宾语从句的住句中主语是第一人称时反意疑问句随从句一致。

9.the great use of school education is not so much to teach you things _____ to teach you the art of learning.

a. as

b. that

c. than

d. but

a

10.no matter how frequently _____ the works of beethoven always attract a large number of people.