题目内容：

Many people have to do their own things every day. Some of them ride bikes and some of them drive cars, so streets look very busy.

This is a street crossing. There are red and green lights at each corner Drivers must watch the lights carefully. when there is a green light the cars may go on. When there is a red light, the cars must stop. They must wait until the light changes to green. Then they can go. Sometimes the cars want to make a right turn or a left turn. They can make a right turn when the light is green or red. But they must wait until the green light is shining if they want to turn left.

But some people are colour-blinded. They can't tell the difference between red and green .These people must not drive. We must keep streets safe.

1.The streets look busy because________.

A.there are so many people and cars or bikes B.the streets are not wide enough

C.many people like travelling D.the streets are fewer than before

2.Drivers must see________clearly at a corner of the street crossing.

A.the people and bikes B.the old and young people

C.the green light and the red light D.the students who are going to school

3.Cars can’t go________.

A.when the green light shows B.when the red light shows

C.when there is no light D.when the light changes

4.A car can turn right when________.

A.there is a green or red light B.there is only a green light

C.there is only a red light D.there is no way

5.If someone is colour-blind, he________.

A.can drive cars B.can see the green colour clearly

C.can’t go to streets D.can’t be a driver