See versus Watch
To see something that comes into our sight that we weren’t looking for. Did you see that bird? – It means you weren’t looking for it, it just appeared. See is used as an inactive word; you just see without any effort. Let us see the difference between See versus Watch.
See is used when you have a visual impression.
E.g. I can see my home over there.
See is used when you understand.
E.g. I see what you mean.
Watch is used when you pay attention.
E.g. Watch the pets while I come back.
Watch is also an inactive word. It is used to look at something carefully, usually at something which is moving.
E.g. I am watching a movie.
Watch is used when you make an effort to look at something but for a longer period of time.