be watchful

See: care, concern
References in classic literature ?
Now, I want to warn you, Helen, of these things, and to exhort you to be watchful and circumspect from the very commencement of your career, and not to suffer your heart to be stolen from you by the first foolish or unprincipled person that covets the possession of it.
Lord Steyne, though a nobleman of the greatest station and talents, was a man whose attentions would compromise any woman; he besought, he implored, he commanded his sister-in-law to be watchful in her intercourse with that nobleman.
Children are naturally attracted to water, and we just need to be watchful every second they are around it,'' said Jim Miller, the club's educational director.
Authorities urged seniors to be watchful for this scam and to notify law enforcement officials of suspicious activity.
We are a group who purports to be aware of the right of older people to be autonomous, as laid down in the NZNO Code of Ethics, and a group who, therefore, should be watchful for paternalistic attitudes creeping into discussions about aged-care issues.
Worshippers were asked not to come to church with handbags and to be watchful of strangers.
Children are naturally attracted to water and we must be watchful every second they are around it.
Officials want Americans to be watchful but not scared.
The teacher should be watchful from the moment the young student stands facing the barre for the first time that the hips are square (not tilted) and the spine is in a neutral position.