it is that he often failed in the exams that makes
2个回答

选C 首先第2个that为强调句It is ...that...中的that 为固定搭配

你可以去掉It is ...that...来看(因为It is ...that...起强调作用 存不存在都不影响句子结构) 这是句子为That he often fails in exams makes his parents worried about him.

这时候个主语从句 在这一句中That he often fails in exams 为主句

所以归纳来说 这是个强调的主语从句

楼上你错了