pretend doing 还是to do

pretend doing 还是to do pretend to be doing pretend to do 和pretend doing 有啥区别 pretend后加doing,还是do,还是to do都可用的话区别在哪? pretend to be done是什么时态?pretend to be doing pretend to have done pretend to have been done呢? “pretend”的用法是什么?比如说:是加to do sth,还是doing sth pretend的用法为什么有的时候用pretend to be doing,而有是却用pretend to do 比如：pretend to be reading,pretend to sleep pretend to do 和pretend to be doing 有什么区别?When the father came home,the naughty boy pretended___ his homework?A to do B to be doing C doing D being done 应该选哪个呢? pretend have done还是pretend to have done? … pretend to do sth … pretend to be doing sth … pretend to have done sth的区别. … pretend to do sth … pretend to be doing sth … pretend to have done sth 的区别是什么、 regret to do/doingregret to do通常用于sb regret to tell/say that...regret doing放到句子中通常要变regret为过去式吗?thanks!补充一个问题pretend doing还是pretend to do谢 Let’s___ we are policemen A.pretend that B.pretend to C.pretending D.to pretend pretend to do 和pretend to be doing有什么区别. pretend to do sth 和pretend to be doing sth造句 是pretend do sth 还是pretend to do sth(假装做某事) I'd like to do还是I'd like doing to be doing 和 doing 有什么不同?如果to be doing表示将来 那么pretend to be doing作何解释?