C．Exercise has something to do with weather.

　　D．People's connection depends on distance.

　　B　解析：推理判断题。根据第四段中"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 the underlined word "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.

　　C　解析：代词指代题。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

　　D　解析：标题归纳题。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。

　　B

　　(2019·合肥高三调研性检测)The San Francisco Giants added a special pitcher(投球手) for the day. It was small-yet fierce-Hailey Dawson, who has a 3D­printed hand.

　　The energetic 8­year­old from Nevada was invited to throw out the first pitch at the Giants game on Sunday. Hailey was born with Poland syndrome, a disorder in which affected individuals were born with missing or underdeveloped muscles on one side of the body. It affected her hand.

With a traditional prosthetic(义肢的) hand potentially costing thousands of dollars, Hailey's mom, Yong Dawson turned to the University of Nevada, Las Vegas for help. She emailed UNLV