Gritting their teeth and breathing heavily, they expend enough energy to lift the piano, even though they are playing a gentle, soft little melody.

他们咬紧牙关，屏住呼吸，耗尽自己最大的能量使得钢琴声音变响。甚至就是在弹奏很温和的、很柔美的曲调，他们也是这么费力。

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McLaren find themselves gritting their teeth again after a very difficult two years.

BBC: Coulthard on Hamilton row

His Israeli opponents on the left are gritting their teeth.

ECONOMIST: Binyamin Netanyahu cocks a snook at the American president