胃穿透性溃疡系指溃疡侵及（）.

A.黏膜层

B.黏膜下层

C.肌层

D.浆膜层

E.黏膜和黏膜下层

He was looking impatient at the visiting salesman, who showed no signs of getting ready to leave.

A．patient

B．patience

C．impatience

D．impatiently