33.His writing is so confusing that it’s difficult to make out _____it is he is trying to express.

问题描述:

33.His writing is so confusing that it’s difficult to make out _____it is he is trying to express.
答案是what 请问这道题结构是什么样的?what it is he is trying to express.象强调句,但又缺that !

what it is = what idea he is trying to express.他想表达的思想/观点.
what- = sth that-/ which-