下列属于讲唱历史的变文是（）A、《伍子胥变文》 B、《维摩诘经讲经文》 C、《张淮深变文

阅读理解。

     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 (化学制品) 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 (汽油) 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 work. They must also be more careful about gas and oil and 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.

1. In the past, the water in Lake Ponkapog was made clean by ______. [ ]

A. forests

B. rain

C. birds

D. fish

2. Chemicals from homes and businesses ______. [ ]

A. are always clean

B. can help the animals

C. are good for the lake

D. get into the rainwater

3. Cleaner rainwater will mean ______. [ ]

A. more boats on the lake

B. more dirty things in the lake

C. a cleaner lake

D. a dirty lake

4. To save Lake Ponkapog, people need to ______. [ ]

A. be more careful about chemicals

B. use the water

C. grow fewer plants in the gardens

D. use more motorboats on the lake

5. The passage is about ______. [ ]

A. boats on the Lake Pankapog

B. why the water is dirty in Lake Ponkapog

C. clean rainwater

D. dirty lakes

判断题：三省六部制调整了中央和地方的关系，保证了君权的独尊。

某种商品上市时，售价为500元，一段时间后该商品售价为300元。产生这种现象的原因可能是                                                                    

①生产该商品的个别劳动生产率降低 ②生产该商品的社会劳动生产率提高 

③该商品得到消费者的喜爱         ④该商品的供应量增加

A．①②

B．③④

C．①③

D．②④

下列说法正确的是（　　）

A．平抛运动的物体速度变化的方向始终是竖直向下的

B．做圆周运动的物体所受各力的合力一定是向心力

C．两个速率不等的匀速直线运动的合运动一定也是匀速直线运动

D．做圆周运动的物体，其加速度不一定指向圆心

小儿用袖套气囊测量上肢血压时，袖套大小应为上臂长度的（）

A.相同

B.1/2

C.1/3

D.2/3

E.3/4