谁能告诉我====动词+ to be doing 和 to doing的区别（下例）

谁能告诉我====动词+ to be doing 和 to doing的区别（下例） to be done=doing? 英语语法求教非谓语动词to be doing 和doing的区别 admit doing和admit to do的区别= = need doing = need to be 它和need to do有什么区别 请问want doing sth =want to be doing吗 为什么有doing=to be done need doing =need to be be said to be doing和be said to have been doing的区别 动词不定式开头的to do=doing吗 【区别】 to sb for doing sth 和 for sb to do sth 的区别 = = be doing和be going to的区别和用法!