is.

1.A serial killer is on the loose!

有个连环杀手正逍遥法外！

2.There is no doubt that he is guilty.

毫无疑问，是有罪的。

3.He is under the delusion that he is Napoleon.

患了妄想症, 认为自己是拿破仑。

4.It is obvious that he is wrong.

显然错了。

5.Motion is absolute while stagnation is relative.

运动是绝对的,而静止是相对的。

6.It is impossible to disguise the fact that business is bad.

生意不好这件事无法隐瞒。

7.It is impossible to disguise the fact that finance is bad.

财政困难这一事实是无法隐瞒的。

8.Her study is based on the hypothesis that language simplification is possible.

她的研究基语言可以简化这样一个假说。

9.My objection is that he is too young.

我反对是因为太年轻。

10.It is obvious that she is very clever.

很明显，她挺聪明。

11.It is logical that the book is expensive.

书贵是很自然的事。

12.It is strange, and yet it is true.

是奇怪, 可是真的。

13.The rarer it is, the more it is worth.

物以稀为贵。

14.That oatmeal is so bland that it is tasteless.

那种燕麦粥平淡无味。

15.There is a general awareness that smoking is harmful.

人们普遍认识到吸烟有害健康。

16.John is very amusing when he is completely befuddled.

当约翰喝得完全糊涂了的, 非常有趣儿。

17.It is distinct that smoking is harmful to health.

很明显, 抽烟对健康有害。

18.It is doubtful whether it is true or not.

这件事的真假是可疑的。

19.The article is very important though it is short.

那篇文章虽然很短，但很重要。

20.It is generally admitted that he is a trustworthy person.

大家一致公认是个可信赖的人。