I don't know what they'll want when they arrive—we'll have to play it by ear.

我不知道他们到达时需要什么—我们只有见机行事了。

《牛津词典》

Neil sat at the piano and began playing, by ear, the music he'd heard his older sister practising.

尼尔坐在钢琴边，凭着记忆开始演奏曾听他姐姐练习过的曲子。

《柯林斯英汉双解大词典》

Play it by ear.

随机应变。

youdao

Play it by ear also means to decide what to do at the last minute instead of making detailed plans.

VOA: special.2009.09.13

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。

麻省理工公开课 - 电影哲学课程节选

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。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

Wilde was plagued by ear problems for much of his adult life, doctors from the University of Cape Town Medical School report in The Lancet.

BBC: Oscar Wilde 'died from ear infection'

It's going to be feet up in front of a TV screen for him more than anything and then we'll have to play it by ear.

BBC: I can complete series - Flintoff

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.

FORBES: The Shape of Things to Come