The doctor recommended that you ________ swim after eating a large meal.

A．wouldn't

B．couldn't

C．needn't

D．shouldn't

铝塑复合管应用于（）。

A．排水、给水(非饮用水)管道

B．工业管道

C．地板辐射采暖系统的盘管

D．饮用水，冷、热水管