Question

4．努力学习是很重要的．It's very important to study hard．．

Answer 1

分析 It's very important to study hard．

解答 答案：It's very important to study hard．这里是说客观事实用一般现在时，表示做某事是怎么样的，故用It's adj+to do sth．很重要very important，努力学习study hard，故答案是It's very important to study hard．

点评 it形式主语，没有意思的，动词不定式真正主语．你看，主语那么长，而谓语就is important 那么短，是不是头重脚轻，为了句子平衡，使用了形式主语，而把真正主语放在后面，所以句型：it‘s+adj+to do 的意思是：做某事怎么样．
尔Doctors think it is important to drink enough water every day．
这时候It is important to drink enough water every day．是宾语从句，作think的宾语．因为think 可以形成think+宾语+宾语补足语，所以此句可改成Doctors think it important to drink enough water every day．
也就是少了be动词is．此时，it是形式宾语
important为宾语补足语to drink enough water every day为真正宾语．
能这样用的，除了find外，常见的还有：find，believe等