The moon wax till it become full, and then wane.

月亮渐渐变圆直至满盈，然后再变亏缺。

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Certainly, some of the facts at hand are valid; for example, the Maya did have a Long Count calendar, pole-shift theory does exist, and solar activity does wax and wane.

当然，有些事实证据是有效的，比如玛雅人的确有一个长记历的历法，地磁反转理论也的确存在，太阳活动的确在减弱等等。

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By measuring changes in the light reflected from the clouds, they found that the clouds appear to wax and wane in prevalence over a 27-day cycle.

通过测量夜光云反射的光的变化，他们发现夜光云从盛到衰的周期大约为27天。

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Like the Moon, asteroids can wax and wane, depending on their position relative to the Sun.

BBC: Asteroid thought to kill dinosaurs may not be guilty

Just understand how sectors tend to wax and wane over a full economic cycle.

FORBES: Watch your sectors

The symptoms of IBD tend to wax and wane, but can seriously debilitate some patients.

BBC: News | Health | Bowel disease drug breakthrough