D
Weather changes when the temperature and the amount of water in the atmosphere change. We can see and feel water coming from the atmosphere when we have rain. But the water must somehow get back to the atmosphere. Meteorologists call this the water cycle.
There are many stages in the water cycle. Rain falls when water vapor in clouds condenses(凝结). Drops of water form and fall to the ground. The water soaks into the ground and feeds streams and rivers. A lot of rain falls into the sea. The heat of the sun evaporates（蒸发） some of the water in the ground and in the rivers, lakes, and the sea. It changes the liquid water into water vapor. The vapor rises onto the air. Water vapor（汽） is normally invisible. On a very damp or humid day, however, you can sometimes see water vapor rising from a puddle(水坑) or pond in a mist above the water. Water vapor also gets into the air from living things. Trees and other plants take in water through their roots and give off water vapor from their leaves. People and land animals drink water and breathe out water vapor. In all these ways the water returns to the air. There it gathers to form clouds and condenses to form rain. The rain falls to earth, and the cycle starts again. It continues even if snow or hail(冰雹) fall instead because both eventually melt to form water. The amount of water vapor in the air depends on the temperature. The air is more moist(潮湿) in the tropics than in the cold polar regions.
68. What is the main idea of the passage?
A. Water cycle.         B. Water vapor.   C. How rain forms.      D. Water, vapor, rain.
69. How many ways of the water returning to the air are discussed in the text?
A. Two.           B. Three.        C. Four.        D. Five.
70. Whether water vapor can be seen or not depends on _______.
A. how much water is evaporated       B. how good your eyes are
C. in which way water is evaporated    D. climate or weather

Ever wonder how much a cloud weighs? What about a hurricane? A meteorologist has done some estimates and the results might surprise you.

Let's start with a very simple white puffy cloud — a cumulus cloud（积云）. How much does the water in a cumulus cloud weigh? Peggy LeMone, senior scientist at the National Center for Atmospheric Research in Boulder, Colorado, did the numbers. "The water in the little cloud weighs about 550 tons," she calculates. "Or if you want to convert it to something that might be a little more meaningful … think of elephants."

The thought of a hundred elephants-worth of water suspended in the sky begs another question — what keeps it up there?

"First of all, the water isn't in elephant sized particles（微粒）, it's in tiny tiny tiny particles," explains LeMone. And those particles float on the warmer air that's rising below. But still, the concept of so much water floating in the sky was surprising even to a meteorologist like LeMone. "I had no idea how much a cloud would weigh, actually, when I started the calculations," she says.

So how many elephant units of water are inside a big storm cloud—10 times bigger all the way around than the "puffy" cumulus cloud? Again, LeMone did the numbers: About 200,000 elephants.

Now, ratchet up the calculations for a hurricane about the size of Missouri and the figures get really massive. "What we're doing is weighing the water in one cubic meter theoretically pulled from a cloud and then multiplying by the number of meters in a whole hurricane," she explains.

The result? Forty million elephants. That means the water in one hurricane weighs more than all the elephants on the planet. Perhaps even more than all the elephants that have ever lived on the planet.

1.The weight of      is NOT mentioned in the passage.

A．a cumulus cloud    B．a tornado          C．a hurricane        D．a storm cloud

2.How did Peggy LeMone feel about the result of her calculations?

A．She found it not convincing.

B．She thought it needed further calculations.

C．She was quite surprised at it.

D．She considered the calculations inaccurate.

3.What can be inferred from the passage?

A．A storm cloud weighs about 200,000 elephants.

B．The water in a hurricane weighs more than that in any other kind of cloud.

C．There are less than forty million elephants living on the earth.

D．The water in the cloud is in very tiny partials.

短文改错（共10小题；每小题1分，满分10分）　

以下标有题号的每一行均有一个错误，请找出，并按下列情况改正：此行多一个词；把多余的词用斜线（\）划掉，在该行右边横线上写出该词，并也用斜线划掉。此行缺一个词：在缺词处加一个漏字符号（Λ），在该行右边横线上写出该加的词。此行错一词：在错的词下划一横线，在该行右边横线上写出改正后的词。

Unlike many other places, our hometown is also facing             76._____

the problem of pollution. Unfortunately, people here have           77._____

realized the importance of protection the natural environment.      78._____

Factories have been taken measures to stop pouring polluted         79._____

water into the rivers. The citizens not longer put waste, such       80._____

as rubbish or human waste into the rivers. Every year,               81._____

a great number trees are planted. As a result,                       82._____

the water in the rivers are becoming cleaner and cleaner.            83._____

The hills around the city were covered with green trees              84._____

and the air here is much more fresher than before.                      85._____

The group of students went to the suburb, did some research work, and ________ the water in the river to see if it had been polluted.

A. proved          B. boiled           C. tested          D. exchanged

短文改错（共10小题；每小题1分，满分10分）

下面短文中共有10处错误，错误涉及一个单词的增加、删除或修改。

增加：在缺词处加一个漏词符号（∧），并在此符号下面写出该加的词。

删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在该词下面写出修改后的词。

注意：1．每处错误及其修改均仅限一词；

2．只允许修改10处，多者（从第11处起）不计分。

Last weekend I went to the Summer Palace as usually. At about noon, I was enjoying my reading near a lake while suddenly I hear someone crying for help. I went up to see what was happening. I was shocking to find a little child struggling in the water in the distance while many peoples were standing by without doing anything. Without any hesitation, I had pushed through the crowd as I took off my coat, but jumped into the water quickly. I managed to reach him and carried him back to safety. To his great relief, the kid was saved.  

I was proud what I had done. I wish everyone can give a hand when someone else is in need.