A young dog should be alert and playful.
Teachers need to be alert to sudden changes in students' behavior.
A little bit of tension is alright - I guess it keeps you alert while driving. (Certificate in Advanced English; C1; Dutch)
The auto manufacturer alerted owners to a problem with the window and asked that they bring the car in to be checked.
Karl Marx alerted us all to the fact that work can cause alienation, and that repetitive tasks, or tasks which do not involve a great deal of interaction with other human beings, can make us feel estranged. (Certificate of Proficiency in English; C2; Italian)
a traffic alert
A severe weather alert for this area is in effect until 6 pm.
Moreover, the Television conveys the most needed day-to-day weather forecasts and any warnings issued by the government agencies, such as flood alerts. (International English Language Testing System; C1; Tamil)
