1.名词作主语
2.代词作主语
3.动名词或动词不定式作主语
4.名词性从句作主语
5.名词短语作主语
6.表距离的地点副词短语作主语
讲解
3.动名词或动词不定式作主语，动词不可以直接当主语，一定要变成动名词或动词不定式，视为名词的对等语，作主语用。
a.动名词作主语，通常用来表示已知的事实或者曾经做过的经历。
例子：听音乐使我快乐。“听音乐”是说话者曾经做过的事，所以用动名词作主语。
Listening to music makes me happy.
Collecting stamps is one of his habits.
b.不定式作主语，通常表示一种意愿、目的或未完成的事。
例子：出国读书是我最大的愿望。从句子中可以知道“出国读书”时一种意愿或没有做的事情，所以应当以动词不定式作主语。
To study aboard is my greatest desire.
到日本游玩是我今年的计划。
To go to Japan for a visit is my plan for this year.
特别注意：不定式或动名词作主语的时候，往往会形成主语太长的现象，故通常用代词It 作形式主语，放在句首。而将真正的主语（亦即不定式或动名词短语）移到句尾。动名词移到句尾时，通常改为不定式短语。
Collecting stamps is his habbit.=It is his habbit to collect stamps.
Listening to music makes me happy.=It makes me happy to listen to music.
To study aboard is my grestest desire.=It is my greatest desire to study aboard.
