单选题It is_______ he often&nbs

问题补充：

单选题Itis_______heoftenfailsinexam_______makeshisparentsworriedabouthim.A.because, thatB.that, thatC.不填, thatD.what, that

答案：

B解析考查主语从句和强调句型。整个句子是强调句型，所以第二空用that引导；去掉it is…that,剩下_______ he often fails in exam makes his parents worried about him.可知_______ he often fails in exam是主语从句，且从句不缺成分，所以用that引导。选B。