Video games are the lifelines to kids who

Video games are the lifelines to kids who
are looking for things that they call “cool and
fun,” but there are many studies that prove video
games are one of the causes why kids (1) are
misbehaved in school and the big reason why
they are getting failing grades.
Lengthy hours in front of gaming could
make it (2) hardly for kids to focus on school
activities.“What we don’t know at this point is
why TV and video games in fact would cause
attention problems,” said Douglas A.Gentile,
who worked on the research.
Researchers,who run the Media Research
Lab at Iowa State University (3) in Ames,
explained that excessive screen time had also
been associated with (4) increases aggression
and,perhaps less surprisingly,expanding
waistlines.
1.A.were misbehaved
B.were misbehaving
C.are misbehaving
D.NO CHANGE
2.A.harder
B.hardest
C.hardness
D.NO CHANGE
3.A.in Ames; explained tha
B.in Ames explained that
C.in Ames.Explained that
D.NO CHANGE
4.A.increase aggression
B.increased aggression
C.increasingly aggression
D.NO CHANGE
The researchers followed a group of more
than 1,300 school-age children,who,joined by
their parents,logged their TV and gaming hours
for over a year.The researchers then asked
teachers to answer questions about how the
children behaved in school—whether they had
difficulty (5) staying within task,for instance,
or often interrupted others.
5.A.staying in task
B.staying on task
C.staying upon task
D.NO CHANGE

1选C,因为动作behave是孩子们发出的,所以不用被动语态,因为是正在发生的常见状况,所以不用过去式.
2选A,因为原文需要形容词,hardly是副词,hardness是名词,hardest是形容词最高级,这种词用于表示某一范围内程度最高的东西,但在这里并没有明确的比较范围,harder是比较级,根据上下文,意思是,与不玩那么长时间游戏的孩子相比,玩游戏的孩子更难集中精力.
3选D,句子主语是researchers,后面跟着一个非限定性定语从句,explained是researchers的谓语动词,没有错误.
4选B,根据句意,“增加的攻击性”,aggression需要形容词来修饰.
5选B,属于固定搭配.