Question

look forward to 与 looking forward to有什么区别

Answer 1

looking forward to do这应该不是个单独的词组吧?是你从某个句子里边摘出来的吧?
应该是 前边有个名次后边跟的looking forward to do吧..举个例子
The money that I am looking forward to have been used up.这个句子就是 类似looking forward to do的,但是 这个歌 to仍然是个介词,后边不能跟动词原型,这个句子中 looking forward to 修饰先行词money 是定语从句中的一部分,后边的have been used up是整句话的谓语.

Answer 2

look forward to
期待；盼望；高兴地等待：
例句: He has been looking forward to going to England for a long time.
好久以来他一直盼望去英国。 　　
Looking forward
looking forward to: 期望,盼望

1. i'll be looking forward to it.
我将期待这一天。

2. Looking forward to your reply.
（书信末尾处）等待你的回复。

3. B: I'm looking forward to that.
我在盼望着那一天