Around the world more people are taking part in dangerous sports and activities. Now, there are people who look for an immediate excitement from a risky activity which may only last a few minutes or even seconds.
I would consider bungee jumping (蹦极) to be a good example of such an activity. You jump from a high place 200 meters above the ground with an elastic (弹性的) rope tied to your feet. You fall at up to 150 kilometers an hour until the rope stops you from hitting the ground. It is said that about 2 million people around the world have now tried bungee jumping. Other activities which most people would say are as risky as bungee jumping include jumping from tall buildings and diving into the sea from the top of high cliffs.
Why do people take part in such activities as these Some psychologists suggest that it is because life in modem societies has become safe and boring. Not very 10ng ago, people’s lives were constantly in danger. They had to go out and hunt for food, diseases could not easily be cured, and life was a continuous battle for survival.
Nowadays, according to many people, life offers little excitement. They live and work in quite safe conditions: they buy food in shops, and there are doctors and hospitals to look after them if they become ill. The answer for some of these people is to look for danger in activities such as bungee jumping.

In bungee jumping, you（）。

A:jump as high as you can B:slide down a rope to the ground C:tie yourself to a rope and fall D:fall without a rope

An apple tree can grow to over 35 feet (25) . Each spring, an apple tree (26) pink and white flowers. (27) a blossom has been fertilized, (28) develops. (29) each apple are small, brown seeds, which can grow into (30) apple trees. Each fall, apple trees (31) their leaves- they are deciduous.
Early in US history, John Chapman (nicknamed Johnny Appleseed) (32) apple seeds around (33) of the USA.Apples are a (34) snack; there is (35) saying, "An apple a day keeps the doctor away./

31（　）

A:fall  B:throw  C:lose  D:getaway

There are many reasons of the tidal action which is a very complicated phenomenon involving many factors all of which must be considered to predict tide in any one place at any one time. The alternate rise and fall of the surface of the seas and the ocean is mainly caused by the attractive force of the moon alone. When the attraction is great, the tide is high; and conversely when the attraction is minimal, the tide is low. Between the high and the low tide is a period of a little over six hours, being called during its rise a flood tide, and during its fall an ebb tide.
The sun also exerts its effect on the tide, being a lit fie less than half as much as the moon, although its mass is so much greater. When the moon and the sun are horizontal, the highest high tide occurs and when they are vertical the lowest low tide takes place.
The wind also plays an important part in the modification of the normal rise and fall of the tide. Thus these factors affect each other, either detracting or adding to the attractive forces to add or subtract from the weight of the tide. But the tides still move inexorably on, rising twice a day, getting a little later each day and posing a problem of correctly predicting their heights and lows.

According to this article, it is clear that the force of the moon（）

A:is not as important as that of the wind B:is less than half as much as the sun C:causes the alternate rise and fall of the surface of the seas D:does not influence the rise and fall of the surface of the seas

What makes it rain Rain falls from clouds for the same reason anything falls to Earth. The Earth’s gravity pulls it. But every cloud is made of water droplets or ice crystals. Why doesn’t rain or snow fall constantly from all clouds The droplets or ice crystals in clouds are exceedingly small. The effect of gravity on them is minute. Air currents move and lift droplets so that the net downward displacement is zero, even though the droplets are in constant motion.
Droplets and ice crystals behave somewhat like dust in the air made visible in a shaft of sunlight. To the casual observer, dust seems to act in a totally random fashion, moving about chaotically without fixed direction. But in fact dust particles are much larger than water droplets and they finally fall. The average size of a cloud droplet is only 0. 0004 inch in diameter. It is so small that it would take sixteen hours to fall half a mile in perfectly still air, and it does not fall out of moving air at all. Only when the droplet grows to a diameter of 0. 008 inch or larger can it fall from the cloud. The average raindrop contains a million times as much water as a tiny cloud droplet. The growth of a cloud droplet to a size large enough to fall out is the cause of rain and other forms of precipitation. This important growth process is called "coalescence".

What can be inferred about drops of water larger than 0. 008 inch in diameter（）

A:They never occur. B:They are not affected by the force of gravity. C:In still air they would fall to earth. D:In moving air they fall at a speed of thirty-two miles per hour.

He found that cool weather is much more favorable for creative thinking than is summer heat. This does not mean that all people are less intelligent in the summer than they are during the rest of the year. It does mean, however, that the mental abilities of large numbers of people tend to be lowest in the summer.
Spring appears to be the best period of" the year for thinking. One reason may be that in the spring man’s mental abilities are affected by the same factors that bring about great changes in all of nature.
Fall is the next best season, then winter. As for summer, it seems to be a good time to take a long vacation from thinking.
Most people’s mental abilities seem to be highest

A:in spring. B:in summer. C:in fall. D:in winter.

Alexander is the first patient at the newly opened RESTART, a video - game and Internet addiction recovery program in Fall City, Wash. , about 30 miles east of Seattle. It’s hard to imagine Alexander, now merrily giving a tour of the woodsy facility, glued to a computer game for more than 16 hours a day, but he says, "It was pretty much all I was doing when 1 was in college. "
Where is RESTART located

A:In Washington C In Fall City B:In Seattle C:In Manhattan.

Alexander is the first patient at the newly opened RESTART, a video - game and Internet addiction recovery program in Fall City, Wash. , about 30 miles east of Seattle. It’s hard to imagine Alexander, now merrily giving a tour of the woodsy facility, glued to a computer game for more than 16 hours a day, but he says, "It was pretty much all I was doing when 1 was in college. "
Where is RESTART located

A:In Washington C B:In Fall City C:In Seattle D:In Manhattan.

Around the world more people are taking part in dangerous sports and activities. Now, there are people who look for an immediate excitement from a risky activity which may only last a few minutes or even seconds.
I would consider bungee jumping (蹦极) to be a good example of such an activity. You jump from a high place 200 meters above the ground with an elastic (弹性的) rope tied to your feet. You fall at up to 150 kilometers an hour until the rope stops you from hitting the ground. It is said that about 2 million people around the world have now tried bungee jumping. Other activities which most people would say are as risky as bungee jumping include jumping from tall buildings and diving into the sea from the top of high cliffs.
Why do people take part in such activities as these Some psychologists suggest that it is because life in modem societies has become safe and boring. Not very 10ng ago, people’s lives were constantly in danger. They had to go out and hunt for food, diseases could not easily be cured, and life was a continuous battle for survival.
Nowadays, according to many people, life offers little excitement. They live and work in quite safe conditions: they buy food in shops, and there are doctors and hospitals to look after them if they become ill. The answer for some of these people is to look for danger in activities such as bungee jumping.

In bungee jumping, you（）。

A:jump as high as you can B:slide down a rope to the ground C:tie yourself to a rope and fall D:fall without a rope