You have to be very alert when you are at your most vulnerable, especially when you are depressed or feeling isolated.

在你最容易受到伤害的时候，你必须非常警惕，尤其是当你感到孤独的时候。

youdao

She is old but still very alert.

她年龄很大，但还是非常机敏。

youdao

Some people are warm and very alert to their senses.

一些人比较热情，对自己的感觉也比较敏感。

youdao

Because it's a very intense job they have to be alert every moment.

因为是高度集中的工作,他们需要时刻保持警惕。

普林斯顿公开课 - 国际座谈会课程节选

In case any of you would like to get involved in research there are very often colleagues of mine or graduate students who are doing interesting projects who will ask me to alert you to the possibilities of working with them.

如果你们希望参与研究,我的同事和我带的研究生,正在做一些很有意思的项目,他们会让我把这些信息告知你们

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

Subjects rated their sleepiness on a scale of 1 (very alert) to 9 (very sleepy) four times in each experiment.

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He also said that at a gathering of the Pope's former doctoral students last summer, Fr Twomey said the Pope was very alert, but very "tired-looking".

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The city looks and feels much better than it did but that does not make the place secure and right now the city is on very, very high alert.

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