Looking forward to可以做主语吗?Looking forward to中的to是介词还是不定式?

Looking forward to可以做主语吗?Looking forward to中的to是介词还是不定式? Looking forward to your looking forward to your Looking forward to your Looking forward to your reply. LOOKING FORWARD TO YOU AGAIN looking forward to the day Looking forward to the final looking forward to see you这句话为什么可以用looking 在商务信函中.结尾用Looking forward to >.这样可以吗?还是用Look forward to >. look forward to doing和looking forward to dolook forward to doing和looking forward to do的区别 I am looking forward to seeing him tomorrow.为什么to后面可以跟动名词. we are all looking forward his coming这样说可以么?look forward to不是固定词组么 为什么Looking forward to your reply.可以写?这里除looking forward to 没第二个动词了呀,为什么要用动名词? looking forward to构成的短语是什么? I will be looking forward to it! I'm looking forward to tomorrow i am looking forward to什么意思