( )12.You should know what to do by now,after ____ told so often.A.being B.be C.been
问题描述：
( )12.You should know what to do by now,after ____ told so often.A.being B.be C.been
请翻译这句话,并详解,为什么选A,
答
after 介词,介词后边跟动词的话要变成ing形式.