Entering the room,I found Mary_____at the desk and_____a letter.

A．seated wrote

B．sitting written

C．seating writing

D．seated writing

工艺设计是属于生产与作业过程中的( )

A．生产技术准备过程

B．基本生产过程

C．辅助生产过程

D．生产服务过程