语法All he does is sit on the chair all day 为什么是does

语法All he does is sit on the chair all day 为什么是does The conductor does not want the dog to sit on the chair.中文 He does nothing but chase girls all day.为什么不用chases呢? 是sit on the chair还是sit in the chair ____ all the food on the table? A.Are B.Is C.Do D.Does does his uncle( )books on the chair? does the shop have all The boy does well in all his l( ).He is a good student. sit on the chair Sit on your chair!Now the chair is ______ you. paul does nothing but all day long Paul does nothing but -- all day long