By the time summer was gone, the ice was down to about 7.2m square kilometres.

而当那年夏季结束时，冰层减至到约720万平方公里。

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By the time they return this summer, the Minnesota troops will have been gone nearly two years.

NPR: Reporter's Notebook: A Delayed Homecoming

In the rainy, summer season, when the tourists are gone and the temperature soars, he devotes himself full time to the cattle side of his business.

FORBES: Notes From A Distant Node