可以做主语,宾语,表语.如：
1.Studying French is not an easy thing.
2.I enjoy studying French.
3.My task now is studying French.亲，是I work for a French company so i think studying French will help me in my job这个句子里做什么成分做主语呀。will help 是动词，做谓语；谓语前面的成分就是主语。