Theylearneditallbythemselves.Thatistosaynobodytoldthem

问题详情：

They learned it all by themselves. That is to say nobody told them ________.

A. how to do it               B. what to do it      C. where to do              D. when to do

【回答】

A

知识点：非谓语动词

题型：选择题