Generally, the reason for such seasonal back-and-forth movement is to seek resources that aren't available within a single area year-round.

一般来说，进行这种季节性往返迁移是为了寻找在一个地区无法全年获得的资源。

youdao

Team location. Is the team co-located (i.e., in a single area)?

团队位置团队成员是否位于同样的地理位置(例如一个单独的区域)？

youdao

Factories should be scattered instead of being concentrated in a single area.

工厂应分散布局而不应集中在一个地区。

youdao

The Raptorex Kriegsteini reportedly was discovered inside a single piece of rock in the Inner Mongolia area of China.

VOA: special.2009.10.13

Or,she can let you try a "single origin" chocolate grown in only one area of the world.

VOA: special.2010.02.17

Fast-growing Winston soon surrounded the much older town of Salem, so in 1913,people in the area voted to combine them into a single place.

VOA: standard.2010.03.18

For efficiency's sake and because of the likely positive spillover effect for a whole village, FXB takes on 80 to 100 families in a single area at one time.

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To be sure, there are more than a few gaping holes in this argument, not the least of which is the fact that the financial crisis that took down asset prices around the globe is not even remotely the same as a natural disaster that hit a single area.

FORBES: How Similar Will the Current Japanese Crisis be to the Credit Crisis of 2008?

The end is that yes, fiscal transfers are indeed the only way in which a single currency area can be kept together.

FORBES: Paul Krugman Shows Why the Euro Cannot Work