题目内容：

The speaker raised his voice just to make himself ( ) Ato be heard B hearing C heard D to hear
可以选A吗

优质解答

make 是使役动词,后面接不定式短语时,to省略掉.但在被动语态时,不定式必须带to.
另一个用法就是 使役动词 可以接 过去分词做受词补语
常用的使役动词还有：let keep help get have
因此应该选 C