A．Lying in bed as long as possible.
B．Taking some sleeping pills to relax.
C．Staying awake as long as they can.
D．Scheduling when to be away or asleep.

A．its effect may linger for almost 10 hours.
B．it disturbs the way people feel in daytime.
C．it accelerates heartbeat and respiration.
D．they may want to take a catnap.

A．Napping for 2 hours is better than for 40 minutes.
B．It does not revive you if the nap lasts too long.
C．You should never take a nap after lunch.
D．The longer you sleep, the better you will feel.