The detective wondered ________．

1. A.
   if there are more than one attacker
2. B.
   what made the man become a murderer
3. C.
   where had the victim been before the murder
4. D.
   how did the murderer come into the house with all window closed

     How do you get to school every day? By bike, by bus or by car? In Chongqing, there will be

3, 000 new school buses on the street by the end of this year.  71             yellow with a big

nose.

    In February 20l0, the Chinese government announced (發(fā)布) the first standards for school

bus safety.   72                .

    In China, besides the bus driver, there should be an adult on the school bus to watch the

students.   73                . The students usually rest or read books on the school bus.

     In America, yellow school buses are very popular. There are about 480,00 school buses in the

country. The older kids sit in the back of the bus. The younger kids sit in the front .   74        

The only adult on the bus is the driver.

     The school bus is important in students' everyday lives. It can keep children safe.   75        .

A school bus saves a lot of gas (汽油) because it can carry a lot of People.

把A~E五個(gè)句子填入文中空缺處，使短文內(nèi)容完整、正確。

If there are more trees, the amount of oxygen in the atmosphere will be ________．

1. A.
   less
2. B.
   fewer
3. C.
   smaller
4. D.
   greater

Thirty years ago, Lake Ponkapog in Hartwell, New Jersey, was full of life. Many birds and animals lived beside the water, which was full of fish. Now there are few birds, animals, and fish. The lake water is polluted. It is in a colour of dirty brown, and it is filled with strange plants.
How did this happen? First, we must think about how water gets into Lake Ponkapog. When it rains, water comes into the lake from all around. In the past, there were forests all round Lake Ponkapog, so the rainwater was clean.
Now there are many homes around the lake. People often use the chemicals (化學(xué)制品)in their gardens. They use other chemicals inside their houses for cleaning and killing insects. There are also many businesses. Businesses use chemicals in their machines of shops. Other chemicals fall onto the ground from cars or trucks. When it rains, the rainwater picks up all the chemicals from home and businesses and then carries them into the lake . They pollute the water and kill the animals.
Boats on the lake are also a problem. Lake Ponkapog is a popular place for motorboats（汽船）. But oil and gas from boats often get into the lake. So more bad chemicals go into the water this way.
People in Hartwell are worried . They love their lake and want to save it. Will it be possible? A clean lake must have clean rainwater going into it. Clean rainwater is possible only if people are more careful about chemicals at home and at other chemicals on the ground. And they mustn’t use motorboats any more on the lake. All these may change people’s lives. Only then can Lake Ponkapog be a beautiful, clean lake again.
【小題1】In the past, the water in Lake Ponkapog was made clean by ________.