| intent(adjective, feature, characteristic, strong, intense) |
| observing(adjective, understanding, kind, friendly, attention) |
| on guard(expression, adjective, idiom, adverb, keen) |
| thoughtful(adjective, kind, reasonable, sensible, delicate) |
| discerning(adjective, understanding, cool, reasonable, keen) |
| wide awake(expression, adjective, sympathetic, wise, attentive) |
| astute(adjective, understanding, cool, kind, keen) |
| guarded(adjective, adverb, reasonable, keen, sensible) |
| on the ball(expression, adjective, idiom, keen, sharp) |
| on the lookout(expression, adjective, idiom, sharp, lively) |
| sharp-eyed(adjective, sympathetic, alert, witting, attentive) |
| conscious(adjective, understanding, cool, keen, sharp) |
| eagle-eyed(adjective, alert, attentive, watchful, sharp-eyed) |
| intelligent(adjective, understanding, cool, sharp, smart) |
| interested(adjective, strong, open, friendly, intense) |
| meticulous(adjective, alert, careful, sober, attentive) |
| obedient(adjective, alert, attentive, compliant, submissive) |
| penetrating(adjective, understanding, strong, sharp, smart) |
| questioning(adjective, alert, attentive, watchful, circumspect) |
| scrupulous(adjective, alert, careful, thoughtful, sober) |