| on guard(expression, adjective, adverb, alert, careful) |
| watchful(adjective, adverb, alert, careful, attentive) |
| observant(adjective, adverb, alert, careful, cautious) |
| on the lookout(expression, adjective, idiom, adverb, alert) |
| vigilant(adjective, adverb, alert, careful, cautious) |
| wary(adjective, adverb, alert, careful, cautious) |
| all ears(expression, adjective, ready, alert, careful) |
| guarded(adjective, adverb, alert, careful, cautious) |
| open-eyed(adjective, alert, careful, cautious, attentive) |
| alert(adjective, adverb, careful, cautious, attentive) |
| attentive(adjective, alert, careful, cautious, suspicious) |
| breathless |
| careful(adjective, adverb, alert, cautious, attentive) |
| cautious(adjective, adverb, alert, careful, attentive) |
| chary(adjective, alert, careful, cautious, attentive) |
| circumspect(adjective, alert, careful, cautious, attentive) |
| custodial |
| glued(adjective, ready, alert, careful, cautious) |
| hawk-eyed |
| heedful(adjective, adverb, alert, careful, cautious) |