We don’t know who for the murder but the policemen will tell us the truth soon.A. is to

问题补充：

We don’t know who for the murder, but the policemen will tell us the truth soon.

A. is to blame

B. is to be blamed

C. is blaming

D. is to be blaming

答案：

A. is to blame

B. is to be blamed

(答案→)C. is blaming

D. is to be blaming

解析：考查固定搭配。sb.be to blame 表示某人应该受到责备。

句意：我们不知道谁为这次谋杀负责，但是警察很快会告诉我们事实的。