To look sharply or intently at someone or something, suggesting a sense of focus combined with scrutiny, as if assessing a potential problem or threat.

To observe or monitor someone or something with a critical or watchful eye, indicating suspicion or a warning to pay attention due to perceived importance.

To stare at someone with a fierce or disapproving gaze, often implying hostility or anger, conveying an emotional reaction rather than just an observation.

To concentrate one's attention on a specific subject or situation, reflecting deep thinking or contemplation about the matter at hand.