Observe (verb)

1. To watch or notice something or someone carefully and attentively.
2. To comply with (a law, rule, or custom).
3. To make a remark or comment on something.

Origin:

Late middle english: from old french observer, from latin observare, from ob- "in front" + servare "to watch".

Examples:

1. She observed the bird through binoculars.
2. He observed the traffic from the bridge.
3. She observed the customs of the local people.
4. He observed the rules of the game.
5. She observed that the sky was clear.