相關(guān)習(xí)題
 0  144470  144478  144484  144488  144494  144496  144500  144506  144508  144514  144520  144524  144526  144530  144536  144538  144544  144548  144550  144554  144556  144560  144562  144564  144565  144566  144568  144569  144570  144572  144574  144578  144580  144584  144586  144590  144596  144598  144604  144608  144610  144614  144620  144626  144628  144634  144638  144640  144646  144650  144656  144664  159627 

科目: 來源: 題型:

【題目】Tom is always the first to ________ school in the morning.

A. reaches B. arrive at C. get D. come

查看答案和解析>>

科目: 來源: 題型:

【題目】Helen didn’t know anything about it ___________her father told her.

A. if B. because C. Nearly D. until

查看答案和解析>>

科目: 來源: 題型:

【題目】— When shall we start?

—Let’s wait ________ the rain stops.

A. if B. as C. until D. since

查看答案和解析>>

科目: 來源: 題型:

【題目】 Your new car looks so nice! Thanks! But I _________ for five years.

A. have bought B. have had C. bought

查看答案和解析>>

科目: 來源: 題型:

【題目】Linda is good _______ English and Chinese.

A. in B.at C. of D. on

查看答案和解析>>

科目: 來源: 題型:

【題目】—What should I do if my parents don’t agree ________ me?

—You’d better find a chance to communicate________ them.

A. with;on B. to;with C. to;to D. with;with

查看答案和解析>>

科目: 來源: 題型:

【題目】

Twinkle, Twinkle Little Star is a lovely song for children, but it has two misunderstandings (誤解). First, stars aren’t little. Some may be Earth-sized, but most are bigger than Jupiter, the largest planet in the solar system (太陽系). Second, they don’t twinkle; they shine. And the brightness and color of the light from each star provide information about its temperature, size and even its age. viewing the stars from Earth is a bit like looking at them through a water filter (過濾器) because the air is thick compared to the emptiness of space. What is more, air is always moving, so starlight appears to be moving, too. The air also makes stars appear dimmer (暗淡的) than they would be if we could see them from space.

If you stop and look at the sky carefully on a dark and moonless night, it’s easy to find color differences among stars. The color of a star is a signal of its surface temperature. The hottest stars are blue, and the next hottest are white. Yellow stars like the sun are next, while red stars are the coolest of the visible (可見的) stars. Many red stars are so dim that people can’t see them at all, and some stars hardly send out any light at all. One reason that stars different in brightness is that hotter stars produce more energy than cooler ones, but another important reason is that some are much bigger than others.

Some stars appear brighter to humans simply because they’re closer. Astronomers rank (排列) the brightness of stars which are seen from Earth by giving them a name known as magnitude (光度) ---the smaller the magnitude, the brighter the object. They have also designed a number that ranks stars according to how bright they are when compared to each other. With a magnitude of minus 26.7, the sun is the brightest object in the sky.

1From the song quite familiar to children, the writer wants to prove that .

A. most stars are smaller than Jupiter

B. Jupiter is bigger and brighter than Earth

C. stars are very large and always shine brightly

D. starlight’s brightness and color are the signs of its temperature

2Magnitude is designed to see .

A. how far a star is from Earth

B. how bright a star is compared to other stars

C. how far a star is from other stars

D. how bright a star is seen from Earth

3Which is the best title of this passage?

A. What do stars look like?

B. Which song do children like best?

C. How to view the stars from Earth?

D. Why are many stars so dim at night?

查看答案和解析>>

科目: 來源: 題型:

【題目】—Must I hand in my homework today? —No, you _________.

A. must B. mustn't C. needn’t

查看答案和解析>>

科目: 來源: 題型:

【題目】The temperature in Beijing is ________ from Shanghai.

A. different B. same C. far D. coming

查看答案和解析>>

科目: 來源: 題型:

【題目】Lets meet at 7:30 outside the gate of ______.

A. the Peoples Park B. the Peoples Park

C. the People Park D. Peoples Park

查看答案和解析>>

同步練習(xí)冊(cè)答案