资料：We never thought we'd say this, but we'd welcome back some chilly weather.
A cool mass of air heads toward the United States from the upper regions of Canada and Alaska this week, according to the National Weather Service.
According to the NWS, a mass of cold air will drop from the Arctic regions to Canada and then the upper Midwest next week.
Temperatures across the Midwest will drop into the 60s and 70s—a sharp difference from the 80 degree and 90 degree temperatures from recent weeks. And the relatively cooler air may be felt as far East as New York and Washington.
The cool breezes may be a welcome relief this time around, but remember the last few times we got hit with Arctic air?
Temperatures in cities including Chicago, Cleveland, New York, and Louisville fell into single-digit and negative territory for long stretches during the harsh winter months of early 2014. But we're sure you remember.
What’s the temperature when the report was written?
本题考查的是细节理解。
【关键词】temperature；when the report was written
【主题句】Temperatures across the Midwest will drop into the 60s and 70s—a sharp difference from the 80 degree and 90 degree temperatures from recent weeks. 中西部地区的气温将下降到60-70华氏度，与最近几周的80-90华氏度的温度有很大的不同。
【解析】本题的问题是“写这篇报道时气温是多少？”。选项A意为“约为60-70华氏度”；选项B意为“为60和90华氏度之间”；选项C意为“华氏60度以下”；选项D 意为“约为80和90华氏度”。根据题目中关键词找到主题句，结合主题句故选D。
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