为什么常用i find it interesting 而不常用i find it's interesting?

为什么常用i find it interesting 而不常用i find it's interesting 为什么常用i find it interesting 而不常用i find it's interesting? 改错because I find it very interesting. I find (it) interesting.为什么it不能改成that或this呢? I find it interesting to learn English.为什么it后面不可加is. I find it interesting to climb mountains.这句话是不是 I find it interesting that Americans haveso many after-schoo I didn't find it interesting 等于什么 i find it interesting to watch football matches 同义句 I find it is interesting to sing(同义句） I find it interesting……造句,谢谢 i find it is interesting to play computer games