-this question is so difficult that we can't answer it -this is such -this question is so -this question is too

`Answer:`

`*` This is such a difficult question that we can't answer it.

`->` Cấu trúc: S + tobe + such (+ a/an) + adj + N(s) + that + S + V

`*` This question is so difficult that we can't answer it.

`->` Cấu trúc: S + tobe + so + adj + that + S + V

`*` This question is too difficult for us to answer.

`->` Cấu trúc: S + tobe + too + adj + for sb + to V

`-` This is + N số ít

`-` a/an + adj + N

`-` Thì HTĐ: `(+)` S + is/am/are + N/Adj

`-` can't + V(bare): không thể làm gì