A.woke up late
B.get much sleep
C.have been worrying
D.all night

A.he thought
B.ahead of
C.Some
D.because

A.he thought
B.ahead of
C.Some
D.because

A.Teens whose parents broke up can't sleep well.
B.Parents can help their children sleep better by restricting their use of technology.
C.Parents have nothing to do with their children's health habits.
D.Teens are unable to perform well at school if they don't get sufficient sleep.

A.insecurity
B.happiness
C.excitement
D.worrying

A.Teens who feel like talking with their parents.
B.Teens who lack a sense of security at school.
C.Teens who have friends sharing their dreams.
D.Teens who feel contented about themselves.

A.parents
B.family dynamics
C.warm relations
D.teens

A.It is necessary for teens to join in sports and positive social activities.
B.Lack of adequate sleep puts teens at risk of performing poorly at school
C.Modern technology has something to do with teens' sleep problems.
D.Teens' sleep is linked to their relationship with people around them.

A.The necessity of being exposed to the harsh reality.
B.The complexity of the world outside.
C.The urgent need for educational reforms.
D.The gap between education and the real world.

A.The necessity of being exposed to the harsh reality.
B.The complexity of the world outside.
C.The urgent need for educational reforms.
D.The gap between education and the real world.