Question

【題目】 You may say that rain comes from clouds, but you can also say that rain is clouds.【1】, you should know the mechanism through which water moves from the Earth to the atmosphere and back again.

Dew point is the temperature at which water vapor begins to condense (凝結) and becomes water droplets that can fall as rain. Dew point can vary anywhere from the 30s (Fahrenheit) to, on rare occasions, the 80s.

【2】. Once the air has cooled past the “dew point", it condenses around a nucleus, which are usually tiny particles of dust, smoke or even salt that are floating in the air. Then tiny water droplets are formed.【3】. If you pay close attention to clouds in the sky, you'll see char they’re constantly shrinking and growing,

Water vapor that has formed clouds is on its way to becoming rain, bur it's not there yet. For now, the water droplets are 80 tiny that the air currents keep them in the air, just as swirling particles of dust can stay in the air.【4】.

When water droplets combine with one another, they become heavier than the uplift of the air around them. Eventually they fall down through the cloud as rain.【5】They attract more water vapor to themselves and grow quickly until they're heavy enough to fall as snow.

A.Rain cloud is formed when there is enough water in the air

B.As warm air rises with the water vapor it contains, it cools

C.If you are curious about what kind of cloud will become rain

D.Sometimes the droplets rise high enough to freeze into ice crystals.

E.The tiny water droplets that initially form are what you see as clouds

F.If you want a better understanding of why rain comes down from clouds

G.As those droplets continue to rise, they have two ways to come back to Earth

Answer 1

【答案】

【1】F

【2】B

【3】E

【4】G

【5】D

【解析】

本文是一篇說明文。文章介紹了雨云是怎么形成的。

【1】根據(jù)第一段的You may say that rain comes from clouds, but you can also say that rain is clouds.(你可能會說雨來自云，但你也可以說雨是云)可知，本文主要介紹雨云是怎么形成的，F項If you want a better understanding of why rain comes down from clouds (如果你想更好地理解為什么雨從云上落下)圍繞這個主題，且承接下文。故選F。

【2】通讀本段及空后的Once the air has cooled past the“dew point", it condenses around a nucleus, which are usually tiny particles of dust, smoke or even salt that are floating in the air. (一旦空氣冷卻過了“凝結點”，它就會在原子核周圍凝結，而原子核通常是漂浮在空氣中的灰塵、煙霧甚至鹽的微粒)可知，本段主要講述雨云的形成原因，B項敘述的是雨云形成的最初狀況，選項中的it cools和has cooled相呼應，且語義As warm air rises with the water vapor it contains, it cools (當熱空氣與它所含的水蒸氣一起上升時，它就變冷了)順承下文。故選B。

【3】根據(jù)上句Then tiny water droplets are formed.(然后形成微小的水滴)中關鍵信息詞form可知，此處就初步形成的水珠展開敘述。選項中的droplets和上句相吻合，且語義The tiny water droplets that initially form are what you see as clouds(最初形成的小水滴就是你看到的云)承上啟下。故選E。

【4】根據(jù)下文Eventually they fall down through the cloud as rain.(最終它們以雨的形式穿過云層落下)及They attract more water vapor to themselves and grow quickly until they're heavy enough to fall as snow. (它們吸引了更多的水蒸氣，并迅速成長，直到它們重到可以像雪一樣落下)可知，此處講述了兩種降水形式。故G項As those droplets continue to rise, they have two ways to come back to Earth (隨著這些水滴繼續(xù)上升，它們有兩種方式返回地球)符合語境。故選G。

【5】根據(jù)下文They attract more water vapor to themselves and grow quickly until they're heavy enough to fall as snow. (它們吸引了更多的水蒸氣，并迅速成長，直到它們重到可以像雪一樣落下)可知，D項Sometimes the droplets rise high enough to freeze into ice crystals. (有時水滴上升到足以凍結成冰晶)緊接其義，語義順承。故選D。

單詞復現(xiàn)法是七選五常用的大題技巧之一，即選項和原文中的某些詞相同或互為詞根詞綴的形式相呼應。比如第3題，E選項中的droplets和上句Then tiny water droplets are formed.(然后形成微小的水滴)中的droplets相呼應。