The look on her face was a definite sign that something was wrong.

一看她的神色就知道出事了。

《牛津词典》

Constantly checking your watch is perhaps the number one sign you're on the wrong bus.

不断地看表也许是最能说明上错车的迹象。

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The first sign that the prediction was wrong came when 2008 turned out to be even calmer than expected.

显示这个预测错误的第一个迹象是，2008年表现得比预测中更为平静。

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You always want to check your signs at the and because it's so easy to get the sign wrong, and I was hoping that it was right here because I wasn't sure, but it turned out to be right.

我们完成计算时，一定要记得检查符号,因为很容易弄错符号，刚才我就不太确定,是否弄错了符号，检查发现没有问题。

麻省理工公开课 - 热力学与动力学课程节选

The drop in reserves was such an unfamiliar twist in the data that Reuters initially reported it with the wrong sign.

ECONOMIST: The balance of payments

But being born under the wrong road sign is a different and perhaps even more intractable problem.

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The first public sign that something was wrong was when more than 100 well dressed young women, described as looking like fashion models, gathered at the airport in the Senegalese capital Dakar, intending to board a plane to Tripoli.

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