题干

在探究“光反射时的规律”实验中,某小组实验步骤如下:

A.把一个平面镜放在水平桌面上,再把一张硬纸板竖直地立在平面镜上,纸板上的直线ON垂直于镜面,如图甲所示.

B.让一束红光贴着硬纸板沿着某一角度射到O点,经平面镜反射,沿着另一方向射出,在纸板上用笔描出入射光线EO和反射光线OF的径迹.改变入射光线的方向,重做两次,换用另一种颜色的笔,记录光的径迹(如甲图)

C.取下硬纸板,用量角器测量NO两侧的角i和角r.

D.纸板ENF是用两块纸板连接起来的,把纸板NOF向前折或向后折,观察反射光线.

根据上述实验步骤,回答下列问题:

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    After finishing my teaching for a school year, I thought that I should go back to Montreal, Quebec, my hometown for a visit. My main goal was to relax in preparation for the challenges of my retirement in the coming year.

    Through my stay in Montreal, I met lots of Chinese who are struggling to succeed and then lead a better life in Canada.

    Some travelled thousands of miles to get knowledge. When I spoke with some of them about the major barrier they had to face after they arrived in Canada, they all talked about the two official languages of Canada. But I was impressed by their ability to express their ideas while switching between English and French.

    Almost all of those people said they often felt homesick. They miss their families and friends. Though Montreal has lots of Chinese restaurants, they long for a home-cooked meal.

    I met some tourists who were trying to realize their childhood dreams of experiencing the life in a developed country. When I asked them if Montreal had lived up to their expectations, they hesitated. They said that reality never agrees with fantasies. However, they were glad to have the opportunity to visit Montreal and didn't regret taking the trip.

    Not all the Chinese people I met were happy. I once met a young lady who met with a gentleman through the Internet. However, to her disappointment, he disappeared after he promised to marry her in Montreal.

    I was served by another Chinese person who could not handle the challenges of studying in an English environment and ended up working in a restaurant with minimum pay.

    Exploring different parts of the world, without any doubt, is an amazing experience. However, one should be realistic when it comes to leaving his hometown to set up a new life in a foreign country. One should take the time to examine the advantages and the shortcomings of the venture before they decide to chase an uncertain dream of achieving success or leading a better life.