When Mary to school?A. is goB. do goC. do goesD. does go

问题补充：

When Mary to school?

A. is, go

B. do, go

C. do, goes

D. does, go

答案：

A. is, go

B. do, go

C. do, goes

D. does, go

解析：goto school,去上学；go是实义动词，变问句需要借助于助动词，且主语Mary是第三人称单数，所以用does，助动词之后跟动词原形。所以选D。