Passage 7

    The rocket engine, with its steady roar like that of a waterfall or a thunderstorm, is an impressive symbol of the new space age. Rocket engines have __1_ powerful enough to shoot astronauts beyond the earth’s gravitational pull and __2 __them on the moon. We have now become travelers space.

    Impressive and complex __3__ it may appear, the rocket, which was invented in China over 800 years __4__ , is a relatively simple device. Fuel that is __5__ in the rocket engine changes into gas. The hot and rapidly __6__ gas must escape, but it can do so only through an opening that __7__ backward. As the gas is radiated with great force, it __8__ the rocket in the opposite direction. Like the kick of a gun that it is fired, it __9__ the laws of nature described by Sir Isaac Newton when he discovered that “for every action, there is __10__ equal and opposite reaction.”

    1. A.shown B.been C.appeared D.proved

    2. A.send B.land C.take D.carry

    3. A.that B.so C.as D.sometimes

    4. A.in advance B.before C.earlier D.ago

    5. A.round B.contained C.stored D.burned

    6. A.heating B.escaping C.expanding D.conducting

    7. A.turns B.goes C.faces D.directs

    8. A.attracts B.leads C.pulls D.pushes

    9. A.states B.proves C.follows D.breaks

    10. A.no B.an C.another D.the

    1.【答案】D

    【解析】因其后接形容詞powerful作表語故應填系詞。shown不是系詞；been和appeared雖可作系詞但與句意不符；而proved可作系詞，意為“證明是”，符合句意。

    2.【答案】B

    【解析】因land on意為“使……著陸”, 而send, take和carry表示“把……送到……上去” 時,常接介詞to, 故應選land.

    3.【答案】C（北京安通學校提供）

    【解析】原句是表示讓步的狀語從句，而且是一個倒裝句，故只能選C as。

    4.【答案】D

    【解析】該句為which引導的定語從句，意為“中國發(fā)明火箭是在距今800多年前。” 句中謂語是一般過去時，故應選D. ago。

    5.【答案】D

    【解析】根據(jù)句子意思判斷，burned正確。來源：www.examda.com

    6.【答案】C

    【解析】根據(jù)句子意思判斷，應選expanding gas膨脹的氣體。

    7.【答案】C

    【解析】faces意為“朝著”。

    8.【答案】D

    【解析】根據(jù)句子意思判斷，應為push“推”。

    9.【答案】C

    【解析】根據(jù)句子意思判斷, follow在這里是遵循的意思。

    10.【答案】B

    【解析】根據(jù)上下文,只能用不定冠詞an。

    Passage 8

    Dalton wondered why the heavier and lighter gases in the atmosphere did not separate as oil and water do. He finally concluded that the constituent __1__ must exist in the form of tiny particles or atoms and that these must be completely mixed together in the __2__. This threw a new light in the laws of definite proportions.It was __3_ necessary to suppose that the atoms could combines into small groups of uniform __5__ and so form more complex substance; thus the mystery of this law was __5__ . Dalton suggested, for example, that carbon monoxide __6__ formed by the one with one pairing of atoms of carbon and oxygen, __7_ carbon dioxide results from a single atom of carbon uniting with two atoms __8__ oxygen. Assuming this to be true, then the definite proportions of Prout’s law would naturally __9_ the relative weights of the many __10__ kinds of atoms.

    1. A.gases B.pieces C.things D.gas

    2. A.sky B.atmosphere C.oxygen D.environment

    3. A.only B.too C.that D.extremely

    4. A.construct B.structure C.piece D.feature

    5. A.solved B.discovered C.broked D.told

    6. A.must B.been C.were D.is

    7. A.while B.when C.therefore D.also

    8. A.from B.in C.of D.for

    9. A.describe B.unit C.mix D.reveal

    10.A.different B.usual C.important D.chemical

    1.【答案】A

    【解析】根據(jù)上文中的heavier and lighter gases可以確定, 本空中應填入“組成的氣體”，即constituent gases。

    2.【答案】B

    【解析】sky意為“天空”，atmosphere意為“大氣”, oxygen意為“氧氣”, environment意為“環(huán)境”,只有B項正確。

    3.【答案】A

    【解析】only necessary的意思是“僅僅是必要”。故A正確。

    4.【答案】B

    【解析】根據(jù)句子意思判斷,這里需要“結構”這個詞，而B合乎題意。

    5.【答案】A

    【解析】solve相當于find a solution or an answer to, 意為“解決”、“解開”,如: solve a problem (a puzzle, a mystery)；discover相當于find something existing but not known before, 意為“發(fā)現(xiàn)”,如: discover a place (a fact, the truth)。因此應選A。

    6.【答案】D

    【解析】因為是表一般規(guī)律，又是單數(shù)，所以用is這個詞。

    7.【答案】A

    【解析】while表示對比。如：Some substances are soluble, while others are not.一些物質(zhì)是可溶的，而另一些物質(zhì)是不可溶的。

    8.【答案】C

    【解析】of表示“含量，分量”。

    9.【答案】B

    【解析】describe意為“描述”；unite意為“結合，合并”；mix意為“(不同的東西)混合在一起”，如：mix flour and water；reveal意為“揭露，揭示”。

    10.【答案】A