We're looking forward to ____the 29th Olympic Games in Beijing.A:visiting B:watching C:looking D:seeing 为什么选B呢?动词不定式不是后面用动词原形么为什么watch后面加了ing啊?

We're looking forward to ____the 29th Olympic Games in Beijing.A:visiting B:watching C:looking D:seeing 为什么选B呢?动词不定式不是后面用动词原形么为什么watch后面加了ing啊?
We're looking forward to ____the 29th Olympic Games in Beijing.
A:visiting B:watching C:looking D:seeing
为什么选B呢?动词不定式不是后面用动词原形么为什么watch后面加了ing啊?

We're looking forward to ____the 29th Olympic Games in Beijing.A:visiting B:watching C:looking D:seeing 为什么选B呢?动词不定式不是后面用动词原形么为什么watch后面加了ing啊?
looking forward to doing
固定用法

补充楼上的：这里的to是介词，而不是动词不定式，所以后面是ing形式而不是原型