You can borrow that bicycle if you want to.为什么用want to ,不是用want it的?

问题描述:

You can borrow that bicycle if you want to.为什么用want to ,不是用want it的?

后面是省略了borrow it.

to 代替整个不定式 to borrow it.
want it 成了“想要某样东西” 了