A
[2019·福州练习] If your friends are happy, it turns out you're more likely to be happy too. If your friends are overweight, that too ups the chances you'll gain weight. Those effects have been shown in studies. And now researchers have identified another seemingly contagious quality: exercise.
The researchers analyzed the running activity of more than a million people worldwide who used an exercise tracking device (装置) for five years. And they used weather patterns as a way to randomly examine different parts of that global network.
“Cities have different weather patterns，” Sinan Aral, a computational social scientist at MIT says. This experiment allowed them to ask: Does a rainy day in New York affect running in San Diego? If the weather in New York causes changes in the running behavior in San Diego, it can really only be happening through the influences of the friends who live between New York and San Diego.
And that is exactly what he and his colleague saw: that the behavior of one city's runners could indeed affect the behavior of runners in another socially connected city. Women tended to be influenced more by the female runners in their networks. And less active runners tended to influence more active runners to run more, but not so much the other way around.
Still, this could be valuable for health professionals. “We have to start thinking of consumers and citizens as networked consumers and citizens. Where they are influenced by and influence their social network in very strong ways, that will change the way a particular intervention (干涉) succeeds or fails.”
In other words, if your prescription is more exercise, the doctors might want to write a prescription for your friends and family, too.
体裁：说明文 题材：调查研究 主题：锻炼也会传染
【语篇解读】 本文主要介绍了锻炼也会传染。
【熟词生义】 up常用义：adv.向上地 本句义：vt.提高，增加
【难句分析】 If the weather in New York causes changes in the running behavior in San Diego, it can really only be happening through the influences of the friends who live between New York and San Diego.
分析：这是一个复合句。If引导条件状语从句，主句中含有who引导的定语从句，who指代先行词the friends，并在定语从句中作主语。
译文：如果纽约的天气造成圣地亚哥人的跑步行为改变，那么这种改变真的只能通过住在纽约和圣地亚哥之间的朋友的影响来实现。
1．Which does the underlined word “contagious” in Paragraph 1 mean?
A．Infectious. B．Excellent.
C．Beneficial. D．Different.
答案与解析：A 考查词义猜测。根据画线词前的“If your friends are happy... you'll gain weight”可知，这些具有传染的特征。故画线词的词义是“传染性的”，故选A项。
2．What can we conclude from the experiment?
A．Weather changes people's feelings.
B．People's behavior affects each other.
C．Exercise has something to do with weather.
D．People's connection depends on distance.
答案与解析：B 考查推理判断。根据第四段中的“that the behavior of one city's runners could indeed affect the behavior of runners in another socially connected city”可推知，人们的行为是互相影响的，故选B项。
3．What does “this” in Paragraph 5 refer to?
A．Women are easier to be influenced by male runners.
B．People in the same city affect each other more.
C．Friends tend to influence each other in exercising.
D．A rainy day in one city affects running in another.
答案与解析：C 考查代词指代。根据第四段的最后两句“Women tended to be influenced more by the female runners in their networks. And less active runners tended to influence more active runners to run more, but not so much the other way around”并结合第五段内容可推知，this指代的是第四段最后两句的内容，即朋友在锻炼时往往是互相影响的，故选C项。
4．Which of the following can be the best title for the text?
A．Think twice before running
B．More exercise benefits health
C．Weather patterns affect running behavior
D．Healthy behavior can spread like illness
答案与解析：D 考查主旨大意。本篇文章开篇提到如果你的朋友快乐，那你也快乐的可能性很大；如果你的朋友体重超重，那你体重增加的概率也会上升，这些效应已经被研究证明。现在研究人员证实了另一个似乎具有传染性的东西：锻炼。故D项最适合作本文的标题。
