Question

4. The teacher came to the classroom and demanded        what had happened.

(tell)

老师来到教室并要求知道发生了什么。

Answer 1

4. to be told/that he ( should) be told demand此处意为"要求"，其后的宾语只可以是名词、代词、不定式或从句，不可用动名词形式。若跟宾语从句时，从句谓语应用"(should + ) 动词原形"结构。