小艇从一个浪头滑向另一个浪头时专挑低回的地方，避开浪峰和波尖，这样才会转过来扭过去穿梭自如。

The coracle, left to herself, turning from side to side, threaded, so to speak, her way through these lower parts, and avoided the steep slopes and higher, toppling summits of the wave.

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这种情况对飞行员来说很糟，因为螺旋桨的尖部接近声速(在海拔较低的温度下大约1200kph)，冲击波造成强烈震动。

And to make matters worse for the pilot, as the tips of the rotor blades approach the speed of sound (around 1,200kph at lower altitude temperatures), shock waves produce huge vibrations.

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美国和法国的研究者支出，大脑中的“尖波涟漪”专门负责记忆，这种涟漪只会在深度睡眠的状态下出现。

According to researcher from American and French, the "Sharp Wave Ripple" in brain which is responsible for strengthen memory can only appear when people fall into deep sleep.

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