1.表述：play by ear
释义1：To be able to play a piece of music after just listening to it a few times, without looking at the notes. （凭听觉记忆演奏）
例句：Wow, George is such a talented piano player! The way he can play pieces by ear after hearing them just once is so impressive!
John can play the piano by ear. If I could play by ear, I wouldn't have to take lessons—or practice!
释义2：To make decisions about what action to take in a flexible way, based on the circumstances. （因时制宜，见机行事）
I haven't decided what to say when he comes. I'll play it by ear.
I' ve had no time to prepare for this meeting, so I' ll have to play it by ear.
If we go into the meeting unprepared, we'll have to play everything by ear.
释义：Nervousness or anxiety felt before one attempts to do something. （在最后时辰掉去勇气，临阵畏缩）
用法：它是名词短语，做谓语和动词get搭配，即：get cold feet。
例句：I wasn't nervous until the morning of my wedding, but everyone assured me that it was just cold feet at the last moment.
Good luck getting her out on stage—she always gets cold feet before a performance.
He planned to participate in the demonstration, but then he got cold feet.
明天，我们进修了2个活泼笼统的雅思词汇：cold feet，play by ear。Hope that you can bear them in your mind.