the big box is too heavy for me to carry.为什么不加it

题目

the big box is too heavy for me to carry.为什么不加it

答案

the big box is too big (for me) to carry too...to是固定句型,表示太···而不能.the box 是主语,后面的 too heavy for me to carry 是一个小的短语在本句充当表语修饰主语,整句话 the big box（主语）is（系）to...