How it works: Grab two books from a trilogy of your choice in each hand.

怎么做：从三本书里选两本书抓在手上，一手一本。

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The choice of proper initial Angle of incidence makes a lateral shearing interference easy to realize between the two beams reflected from the front and back surfaces of a plane-parallel plate.

通过选择合适的初始入射角，使从平板前后表面反射的两光束实现剪切干涉。

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Units can be constructed from a single alarm channel to a maximum of 128 channels, in any format, with ultra-bright LED illumination as standard and with a choice of two window sizes and six colours.

模块可以组装成任意结构，从有单一的警报主频到最多的128警报主频，并且有超亮的LED灯彩标准以及两种窗口型号和六种颜色的选择。

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When offered a choice between two males of their own species, one of which came from the overlap zone and one of which did not and thus had the primitive plumage females of both species consistently preferred males from the overlap.

ECONOMIST: Evolution

The latter success seems to be a response to two years of pressure from the coalition of 37 Beijing-based nonprofits, the Green Choice Alliance.

FORBES: How Green Are Your Gadgets?