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

I also issued them a passport, put their picture in it, had them sign their names, check to see how they know their addresses.

我还给他们每人发了一个护照，把他们的照片放在里面，并让他们签名，从而检查他们。

麻省理工公开课 - 媒体、教育、市场课程节选

Always check your sign at the end.

一定要记得检查符号。

麻省理工公开课 - 热力学与动力学课程节选

I differentiate a second time and check the sign, so the second order condition, I differentiate this expression again with respect to q1.

我们对它进行二次求导然后看符号,这个式子的二阶导数,就是一阶导数再对q1进行求导

耶鲁公开课 - 博弈论课程节选