In China，more and more middle school students are getting   56  sleeping time than before．Most students sleep less than nine hours every night, because they have much homework to do．Some homework    57   by their teachers，and some by their parents. Also, some students don’t know    58   to save time．They are not    59   enough while they do their homework, so it    60  them a lot of time．Some students spend too much time    61 TV or playing computer games．They stay up very late．Some students have to get up early every morning   62  weekdays to get to school on time by bus or by bike． It can be a long way from home to school．

Schools and parents should cut down some of the homework    63   our children can enjoy more than nine   64  sleep every night for their health．For children, we should make best use of our time. When we have enough time for sleeping，we will find   65  much better for both our study and health. 

(    )小题1:A．that        B．this         C．It

不是传导性聋常见病因的选项是（）。

A.外伤

B.炎症

C.噪音

D.异物或其他机械性阻塞

E.畸形