It's a __day（）

ely.

A.What nice it is

B.How nice it is here

C.It is like spring here

D.What a good day here

A.death

B.Chaucer’s birth day

C.rebirth

D.the young sun

A．The earth spins and travels around the sun at the same time

B．One day is the time it takes the earth to travel around the sun once

C．One year is the time it takes the earth to spin around once

D．It is impossible to measure the earth’s movement．

m, which is dark by day and pale by night.The crab's changing color follows a regular twenty-four hour plan that exactly matches the daily rhythm of the sun.

Does the crab actually keep time, or does its skin simply answer to the sun's rays, changing color according to the amount of light that strikes it？ To find the reason out, biologists kept crabs fo a dark room for two months.Even without daylight the crab's skin color continued to change exactly on time.

This characteristic probably developed gradually in answer to the daily rising and setting of the sun, to help protect the crab from sunlight and enemies.After millions of years it has become completely regulated inside the living body of the crab.

The biologists noticed that once each day the color of the fiddler crab is especially dark, and that each day this happens fifty minutes later than on the day before.From this they discovered that each crab follows not only the rhythm of the sun but also that of the tides.The crab's period of greatest darkening is exactly the time of low tide on the beach where it was caught!

21.The fiddler crab is like a clock because it changes color ().

A.in a regular 24-hour rhythm

B.in answer to the sun's rays

C.at low tide

D.every fifty minutes

22.The crab's changing color ().

A.tells the crab what time it is

B.protects the crab from the sunlight and enemies

C.keeps the crab warm

D.is of no real use

23.When the fiddler crabs were kept in the dark, they ().

A.did not change color

B.changed color more quickly

C.changed color more slowly

D.changed color on the same timetable

24.The crab's color-changing ability was probably developed ().

A.in the process of evolution

B.over millions of years

C.by the work of biologists

D.both A and B

25.The best title for this selection would be ().

A.The Sun and the Tides

B.Discoveries in Biology

C.A Scientific Study

D.A Living Clock

Mrs.Park: 1 ___________ in California？

Student A: It’s always warm.

Mrs.Park: 2 ___________ there？

Student B: The temperature is always about 78 degrees.

Student A: That’s the temperature in Fahrenheit.It’s the same as 26 degrees Centigrade.

Mrs.Park: 3 __________ in Seattle？

Student B: 4 _______, because it rains almost every day and people are very happy when the sun 5 _______.

ch longer than that of sunrays. These longer heat waves cannot pass through the atmosphere as easily as the short waves coming from the sun. Similarly, radio stations that transmit programs to distant countries broadcast in short waves, which can travel all around the world. Stations that broadcast local programs send out longer waves, which can be received more easily, but only in a limited area.

(83) Heat waves, rising from the earth, meet resistance in the atmosphere from the water vapor there. Many if the waves are stopped by the water vapor can not get back out into space. The atmosphere, when it is warmed up, also adds some heat back to the earth's surface.

When the sun's rays strike water surface, some of the water becomes absorbed by the air as water vapor. The warmer the air is, the more vapor it can hold. When the air has absorbed its maximum amount of vapor, it is said to be saturated. If the air is then cooled, some of the vapor will condense and clouds will form. (84)These clouds, will contain drops of water at temperatures above freezing, or ice crystals at temperatures below freezing.

Clouds can greatly affect the temperature of the earth's surface. When there are many clouds in the sky, all of the sun's rays can not reach the earth. The cloudy day, then, will be cooler than the cloudless day. Clouds also prevent the earth from cooling off rapidly at night. For this reason, countries such as the British Isles, which are often covered by clouds, have a relatively constant temperature. The weather in these cloudy areas is neither very hot in summer nor very cold in winter. On the other hand, places such as deserts, which have few or no clouds, have very sharp variations in temperature—between night and day as well as between summer and winter.

Radio stations that transmit programs to distant countries send out waves that resemble______.

A．heat waves rising from the earth

B．waves absorbed by water vapor

C．waves sent out by radio stations that transmit local programs

D．the rays sent out from the sun

Passage Two

Questions 26 to 30 are based on the following passage.

Tides are created mainly by the pull of the moon on the earth. The moon's pull causes water in the oceans to be a little deeper at a point closest to the moon and also at a point farthest from the moon, on the opposite side of the earth. These two tidal “waves” follow the apparent movement of the moon around the earth and strike nearly every coast line at intervals of about twelve hours and twenty-five minutes. After reaching a high point, the water level goes down gradually for a little more than six hours and then begins to rise toward a new high point. Hence, most coast lines have two tides a day, and the tides occur fifty minutes later each day. Differences in the coast line and in channels in the ocean bottom may change the time that the tidal wave reaches different points along the same coast line. The difference in water level between high and low tide varies from day to day according to the relative positions of the sun and the moon. The sun also exerts a pull on the earth, although it is only about haft as strong as the pull of the tides arise higher and when they pull at right angles to one another. the tide is lower. The formation of the coast line and variations in the weather are additional factors which can affect the height of tides. Some sections of the coast are shaped in such a way as to cause much higher tides than are experienced in other areas. A strong wind blowing toward the shore may also cause tides to the higher.

Which of the following is right according to the passage？

A. Some coast lines do not have two tides each day.

B. Tides are not affected by the shape of coast line.

C. The sun has as much effect on tides as does the moon.

D. Tides usually rise to the same land day after day.

rs and planets？ Stars can give out heat and light, but planets cannot.

The sun is one of the stars.Some planets are balls of rock and some are balls of gas.We live on the planet earth.The earth spins around once every day to give us day and night.The earth goes around the sun once every year to give us different seasons.

There are eight planets moving around the sun.We call the family of the sun and its planets the solar system.Mercury is the nearest to the sun, so it is very hot.It is the smallest planet.Venus is very bright and hot.It is the nearest to the earth.Mars is covered with orange-red desi and rocks, so it looks like a red star in the sky.It has seasons like the earth.Jupiter has more than 16 moons (卫星)and it is the biggest and heaviest planet.Saturn has more than 22 moons.The other planets, such as Uranus and Neptune, are all very far from the sun and very cold.We need a telescope (望远镜) to see them.

(1)The sun can give us().

A.heat and water

B.heat and light

C.light and air

D.rock and water

(2)The Chinese meaning of "spin around" is().

A.飞行

B.行驶

C.环绕

D.旋转

(3)The earth goes around()once every year to give us different seasons.

A.the moon

B.Mars

C.Jupiter

D.the sun

(4)Mars looks red in the sky because().

A.it is covered with orange- red dust and rocks

B.it has seasons like the earth

C.it is the nearest to the earth

D.it is covered with red water and dust

(5)Which is NOT true according to the passage？ ()

A.Jupiter is the biggest and heaviest planet.

B.Uranus is very far from the sun and very cold.

C.The revolution(公转) of the earth gives us different seasons.

D.We call the family of the sun and its planets the Milky Way.

Text 2 To understand how astrology works, we should first take a quick look at the sky. Although the stars are at enormous distances, they do indeed give the impression of being affixed to the inner surface of a great hollow sphere surrounding the earth. Ancient people, in fact, literally believed in the existence of such a celestial sphere. As the earth spins on its axis, the celestial sphere appears to turn about us each day, pivoting at points on a line with the earth's axis of rotation. This daily turning of the sphere carries the stars around the sky, causing most of them to rise and set, but they, and constellations they define, maintains fixed patterns on the sphere, just as the continent of Australian maintains its shape on a spinning globe of the earth. Thus the stars were called fixed stars.

The motion of the sun along the ecliptic is, of course, merely a reflection of the revolution of the earth around the sun, but the ancients believed the earth was fixed and the sun had an independent motion of its own, eastward among the stars. The glare of sunlight hides the stars in daytime, but the ancients were aware that the stars were up there even at night, and the slow eastward motion of the sun around the sky, at the rate of about thirty degrees each month, caused different stars to be visible at night at different times of the year.

The moon, revolving around the earth each month, also has an independent motion in the sky. The moon, however, changes its position relatively rapidly. Although it appears to rise and set each day, as does nearly everything else in the sky, we can see the moon changing position during as short an interval as an hour or so. The moon's path around the earth lies nearly in the same plane as the earth's path around the sun, so the moon is never seen very far from the ecliptic in the sky. There are five other objects visible to the naked eye that also appear to move in respect to the fixed background of stars on the celestial sphere. These are the planets Mercury, Venus, Mars, Jupiter, and the Saturn. All of them revolve around the sun in nearly the same plane as the earth does, so they, like the moon, always appear near the ecliptic. Because we see the planets from the moving earth, however, they behave in a complicated way, with their apparent motions on the celestial sphere reflection both their own independent motions around the sun and our motion as well.

第26题：The ancient people believed that ________.

[A] the earth was spinning on the axis of the sky

[B] the sky was a hollow sphere spinning around the earth

[C] the patterns of stars on the sky would never change

[D] the stars around the sky were not stationary

air (1)_____ the oxygen without which neither plants nor animals (2)_____ live. Its movements, temperature and pressure (3)_____ the weather, and it is a vehicle (4)_____ the clouds of water vapor (5)_____ condense and fall as rain. It forms a blanket which (6)_____ us from the extreme heat of the sun during the day and (7)_____ the extreme cold when the sun has (8)_____

It is chiefly (9)_____ air that sound travels, so that if there were no air we should (10)_____ practically nothing. The atmosphere is held (11)_____ the earth's surface by the gravitational pull of the earth—that is, it has weight. High up it is thin (12)_____ near the surface it is compressed by the (13)_____ of air above, and is more dense. The weight of air pressing (14)_____ each square inch of surface at sea-level is nearly (15)_____ pounds, which means that the total force (16)_____ the skin of an average man is about 30,000 pounds. He is not, (17)_____ this because the pressure is equal in all directions and the pressure inside him is equal (18)_____ -that without, but should he go up in a balloon to a height at which the outside- pressure is (19)_____ he would suffer acutely. It is (20)_____ this reason that the cabins of aeroplanes are 'pressurized'.

A．forms

B．contains

C．consists

D．fills