公共英语PETS二级阅读复习(51)

　　Have you ever looked up at the night sky and wondered why the stars twinkle? In fact, the stars themselves do not actually twinkle--the illusion is caused by the numerous layers of atmosphere between us and them.

　　你是否曾抬头仰望夜空，思索着星星为什么会一闪一闪呢?事实上，星星本身并不能闪烁，感觉到星星在闪烁其实是一种幻觉，而这种幻觉是由于我们和星星之间的多层大气所造成的。

　　公共英语PETS二级阅读复习(52)

　　With the advent of freezers and mechanical refrigeration, ice cream production soared, with 150 million gallons of ice cream being made in the U.S. in 1919. Today, one simply has to walk down to his or her local ice cream shop to enjoy ice cream. The only difficulty is which flavor to choose.

　　有了冰箱和冷藏技术之后，冰淇淋制造业也随之蓬勃发展，一九一九年美国制造了一亿五千万加仑的冰淇淋。今天，只要走几步路，你就可以在住处附近的冰淇淋店好好地享用一番了，唯一的困难是选择何种口味的冰淇淋。

　　公共英语PETS二级阅读复习(53)

　　But why do stars shine in the first place? A star is made when a huge cloud of mostly hydrogen gas collapses. As the cloud gets denser, it also gets hotter. Finally, the center of the cloud gets so hot that it begins to produce its own energy through nuclear reactions. The temperature in the middle of our sun is about fifteen million degrees. That's hard to imagine!

　　不过星星为何会发光呢?当一个主要由氢气组成的星气团崩解时，一颗星星就形成了。当云变得更绸密时，温度也会跟着升高，最后，星云的中心温度不断升高，然后就形成核反应所产生的能量。太阳中心点的温度大约是一千五百万度，真是令人难以想象。

　　公共英语PETS二级阅读复习(54)

　　The planets, however, seem to twinkle less. They are much closer to the earth, so they appear as relatively broad reflective bodies rather than points of light. Because of this, the twinkling effect is very small. This is one way to tell whether you're looking at a planet or a star.

　　然而行星似乎不怎么闪烁。由于距离地球较近，行星看起来像是会反射的球体，而不是一个光点。因此行星闪烁的效果不甚明显。这点有助于辨别你所看到的究竟是行星还是星星。

　　公共英语PETS二级阅读复习(55)

　　As the air in the earth's atmosphere swirls around over our heads, the light passing through it from space to earth is continually bent in different directions. This causes a rippling effect, like when you observe something underwater, or look down a hot road in the summer. To our eyes, the stars appear to twinkle.

　　当大气中的空气在我们上方旋动，光线穿过大气层，从太空照射到地球，并且往不同方向折射，这样便形成了涟漪般的效应，这就好像你看着水底下的东西，或是在夏天里望着炙热的马路，道理是一样的。所以，在我们眼中，星星在闪烁。