1. I think (that) it is difficult to learn it, but I decide to learn it well.这个句子,think后面是宾语从句,that不做成分,可以省略。所以it is difficult to learn it, but I decide to learn it well.是一个宾语从句。如果是你说的去掉it。那应该是I think itdifficult to learn, but I decide to learn it well。 这时就没有宾语从句了。but连接两个并列句。I think itdifficult to learn 中的it是形式宾语。“我认为它比较难学...