I found __ very important to learn English well.选择it 还是 it's

I found __ very important to learn English well.选择it 还是 it's i found __ very hard to learn english well(A:them b:it is c: I found it important to learn English.(改为同义句） I found __ __ I find it very important to learn English well.A.So I am B.S It's important to learn English well. He found that it was important to learn English well. 1、I found it very hard to learn English well.(同义句) I found _ We found it was very useful to learn English well I found it very useful to learn English well.=___ ___ ¬u It's important for us to learn English well. It's important to learn English well.变成同义词 I found it very difficult to learn maths well.