In China,more and more middle

In China,more and more middle
( )46.What makes most students sleep less than nine hours every night?A.Watching TV .B.Playing computer games.C,Doing their homework .( )47.Who else gives children some homework to do except their teachers?A.Their parents.B.Other students.C.The children themselves.( )48.How many hours of sleep are good for students' health?A.Less than 9 hours.B.Over 9 hours.C.Only 9 hours.( )49.What would happen to a student who often goes to bed late and gets up early?A.He would fall asleep in class.B.He would do well in study.C.He would finish his homework fast.( )50.Which of the following is NOT true?A.Some students are so careless that they spend lots of time on their homework.