—How many hours do you sleep every day ?—.A. Once a dayB. EightC. UsuallyD. Three times

问题补充：

—How many hours do you sleep every day ?

—.

A. Once a day

B. Eight

C. Usually

D. Three times

答案：

A. Once a day

(答案→)B. Eight

C. Usually

D. Three times

解析：句意：——你每天睡多少小时？——八小时。once a day一天一次，eight八，usually通常，three times三次。How many hours是询问多少小时，所以选B。