be carefully looking out for something, especially a possible danger
留心，注意；提防
stay on the lookout for danger or trouble
放哨
protect oneself (or someone else) against danger from an unexpected quarter
保护自己（或他人）（以防意外的危险）
(poetic/literary)the hours of night, portrayed as a time when one cannot sleep
(诗／文)夜间醒着的时间
ensure that one is aware of the time in order to avoid being late
注意时间
spend time observing other people going about their business
观察他人在做什么
To be careful or on the alert; take care.
戒备：提防或戒备；注意
To be in charge of; superintend.
监督
To be careful
注意留神
had to watch it when I stepped onto the ice.
当我走上冰面就不得不留神了
To act or proceed with care and caution.
谨慎行事：小心谨慎地行动或前进
To behave as is demanded, required, or appropriate.
按要求或合适地表现