A pilot must remain vigilant at all times.
飞行员必须随时保持警惕。
1.不睡的,时时警惕着的,警戒着的;极留神的;警醒的
1.watching a person or situation very carefully so that you will notice any problems or signs of danger immediately
1.It's simply a fun little holiday, but a holiday on which one must remain forever vigilant, for he may be the next April Fool!
这只是一个有趣的假期，但假期的其中一个必须永远保持警惕，因为他可能成为下一个愚人节！
2.Our congress should call upon the whole Party to be vigilant and to see that no comrade at any post is porced from the masses.
我们的代表大会应该号召全党提起警觉，注意每一个工作环节上的每一个同志，不要让他脱离群众。
3.Describe a situation in which you felt it necessary to be very attentive and vigilant to your environment.
描述一个你认为有必要对环境非常专心和警觉的情形。
4.Medical crises will inevitably arise; the child must be vigilant for a hospital's bad habits when caring for elderly patients.
医学危机将不可避免地出现；当子女照料晚年的双亲时，子女必须警惕医院的不良习惯。
5.However, he said the incident makes clear the United States must remain vigilant against possible attacks.
但他表示，这一事件显示美国必须对可能发生的袭击保持警惕。
6.'The American people need to understand the threat that they face and their responsibility to remain vigilant, ' he said.
他说，美国人民需要了解他们面临的威胁以及他们保持警觉的责任。
7.Numerous fishing traffic, including the unlit ones may be met while en route, hence vigilant look out to be maintained at all times.
航路上可能会有大量的渔船，包括不点灯的渔船，航行中必须时刻保持警惕和谨慎的了望。
8."We have to continue to be vigilant, as I said, vaccination is not the total solution for equine influenza, " he said.
我们必须继续保持警惕，我认为，种痘不是马流感完整的解决手段。
9.Parents need to be especially vigilant not to say something casually that they may be alarmed to hear later in the mouths of their children.
父母要特别注意不要信口开河，以免日后惊讶地发现同样的话在孩子们的口中说出来。
10.We're obviously going to be vigilant over the next couple of months, in looking at the ways that people are doing that.
当然，在接下来的几个月内，我们会非常关注对人们对此的反应。