look forward to后面一定要用v-ing吗?

look forward to后面一定要用v-ing吗? look forward to后面都可以接什么 look forward to 的后面什么时候动词不用加ing? look forward to 后面接什么动名词吗》？ 急look forward to与Look forward look forward to等于 Look forward to造句 look forward to 造句 look forward to look forward to,wonder look forward to your look forward to doing. look forward to look up/look forward to LOOK forward TO 还是LOOK FORWARDS TO look forward to和look forward to doing的区别 look forward to 的用法 look forward to your letter