题目

In Britain and other countries, young people sometimes take a gap year, a year off between high school and college. This idea never gained a big following in America. Recent news reports have suggested that interest may be growing , though there are no official numbers. Charles Deacon, Dean of Admissions at Georgetown University in Washington, DC estimate that in the current first-year class of 1600 students, only about 25 decided to take a year off. He says this number hasn’t changed much over the years. Mr. Deacon says the most common reason for taking a gap year is to have a chance看云识天气||||我们还可以根据云上的光彩现象，推测天气的情况。在太阳和月亮的周围，有时会出现一种美丽的七彩光圈，里层是红色的，外层是紫色的。这种光圈叫做晕。日晕和月晕常常产生在卷层云上，卷层云后面的大片高层云和雨层云，是大风雨的征兆。所以有“日晕三更雨，月晕午时风”的说法。说明出现卷层云，并且伴有晕，天气就会变坏。另有一种比晕小的彩色光环，叫做“华”。颜色的排列是里紫外红，跟晕刚好相反。日华和月华大多产生在高积云的边缘部分。华环由小变大，天气趋向晴好。华环由大变小，天气可能转为阴雨。夏天，雨过天晴，太阳对面的云幕上，常会挂上一条彩色的圆弧，这就是虹。人们常说：“东虹轰隆西虹雨。”意思是说，虹在东方，就有雷无雨；虹在西方，将有大雨。还有一种云彩常出现在清晨或傍晚。太阳照到天空，使云层变成红色，这种云彩叫做霞。朝霞在西，表明阴雨天气在向我们进袭；晚霞在东，表示最近几天里天气晴朗。所以有“朝霞不出门，晚霞行千里”的谚语。                        （节选自《看云识天气》） 7、本段说明的中心是什么?用文段中的原话回答。 答：                                                                         8、按照云的不同光彩，云可以分为哪四种?它们的色彩是怎样的? 答：                                                                         9、“朝霞不出门，晚霞行千里”的谚语告诉我们什么样的天气规律? 答：