The way people spend their leisure time is what makes people ______and reveals who they are.

A．Pieces of jokes are written in almost every WC.
B．There are some meeting announcements on the billboard.
C．All kinds of messages are written on the paths.
D．Some people are shocked by the meeting announcements.

A．the surface of the sea is a dead flat on a calm day
B．the sea waves are caused by a variety of factors
C．it’s a good idea to swim uphill, sometime
D．hills and valleys only exist on land