The paragraph should contain only one central idea. this can be stated in a topic sentence.

一个段落只能表达一个中心思想，往往在主题句中提及。

youdao

And positive feedback is one of the things that's central to the whole idea of swarm intelligence as well.

积极的反馈是整个群体智慧的核心的想法之一。

youdao

We've got good wingers with a lot of pace and very experienced central midfield players, but you can't change tactics for one player, and the manager has an idea of how he wants to play.

我们有好的，速度快的边锋，以及老道的中场，但是并不能根据一个球员而改变球队的战术，毕竟，教练有他自己的想法。

youdao

And the central idea is that there is one proper response to God's mighty acts on behalf of Israel, and that is resolute observance of the book of the Torah of Moses, without intermingling with the peoples that remain.

其中心思想是没有恰当的回应,对于上帝代表以色列的无上举动，还有对摩西五经的绝对遵守，不可与你们中间所剩下的这些国民搀杂。

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This was one of the first attempts by a central bank to try out the big new idea of the postcrisis world: macro-prudential regulation.

WSJ: There's a Feeling of Instability Bubbling Up

And Blair's idea of choice is still one handed down from on high by central government through bureaucratic target-driven initiatives like 'Choose and Book'.

BBC: NEWS | UK | UK Politics | In full: George Osborne speech

Not central air-conditioning, mind you, but window units that one could leave off if the idea of being comfortable in summer were despicable.

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