老师跟我们讲look forward的用法时说有look forward + to do和look forward to

look forward to用法 还是不懂,look forward to do和 look forward to doing用法的区别 look forward to 的用法 look forward to的用法? look forward to和look forward to doing的区别 look forward to doing和looking forward to do look forward to doing sth和look forward to do sth的区别? 急look forward to与Look forward look forward to 的用法是什么? 'look forward to'的用法，意思，结构 look forward to,wonder look forward to造句