Today the canal is still being used. Ships can be seen moving on ______ water now and then. But it is no longer ______ busy water highway.

A．a, the

B．the, /

C．/, a

D．the, a

商陆的功效是

A．去积杀虫

B．润肠通便

C．泻下利水

D．清肝泻火