it 形式宾语，to后面的是真正宾语。

常见的形式宾语有：find/think ＋ it/them ＋形容词 to do sth.

如：I think {#blank#}1{#/blank#} English. 我认为学习英语很难。

{#blank#}1{#/blank#} {#blank#}2{#/blank#}, he doesn't like to stay here.

The UN {#blank#}1{#/blank#} only 51 member counties at the very beginning when it was set up. Now it has 193 member countries.

Wow, you have {#blank#}1{#/blank#} {#blank#}2{#/blank#} {#blank#}3{#/blank#}books {#blank#}4{#/blank#}I have!

 Lucy usually {#blank#}1{#/blank#} rice and vegetables {#blank#}2{#/blank#} lunch.