by ear

基本解释

But even those sightless from birth acquire language by ear without difficulty in infancy, and having done so lead relatively ordinary lives.
但是，实际上，那些生来就失明的人在婴儿期时期就毫不困难的通过耳朵获取了语言。正因如此，他们过着相对正常的生活。
Watch which types of habitats seem to have the most birds nearby, and learn to listen for bird sounds and songs that can help you begin birding by ear.
看看哪种类型的栖息地附近鸟儿最多，学会听鸟儿的叫声和歌唱，这可以帮你学会“用耳朵观鸟”。
Bird By Ear: There is no better season to learn birding by ear than spring, when many returning migrants use song to stake their territories and claim mates.
靠听觉观鸟：想要学习用耳朵来“观”鸟，没有比春天更合适的季节了，因为这时很多刚回来的候鸟会用歌声来标界它们的领地和吸引异性。

Play it by ear also means to decide what to do at the last minute instead of making detailed plans.
He learns music by ear and maybe plays records over and over again.
他用耳朵来学习音乐,可能就是一遍又一遍地放录音。
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And bathing inside the inner ear fluids where they become stimulated by sound waves and acceleration forces.
毛细胞悬浮在内耳液中,接受声波和其它外力的刺激。
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It can be done by ear, but musical notation helps by turning sound into a visual medium, a common language for the consistent creation and sharing of the music.
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