The difference between "hear" and "listen", and "see", "look at", and "watch"

The basic point is whether the subject is focusing their attention or not. With "hear", your ears are not focused on the object, but with "listen", they are.

• I can hear the people talking in the other room. <- I'm not paying attention to it.
• I'm listening to the people talking in the other room. <- I'm paying attention to it. I might want to know what they are saying.

Visually, there's a third distinction. Like with your ears, "see" means a lack of focus. Both "look at" and "watch" mean the eyes are focusing on something. The difference between the latter two is that "watch" is only for something that is moving or expected to move.

• I'm trying to watch TV, but all I can see is your big head in front of it. <- The image on the screen is moving, and I'm not trying to focus on your big head.
• I see the TV flickering across the room, but I don't want to even look at it. <- I'm aware of the TV, but I don't want to focus on it.
• Please watch my things. <- I'm going out, and I expect that my things will move (or be moved by a thief) while I'm out, unless someone else watches them for me.

Putting them all together, you can make a story like this:

• I was listening to music when I heard the phone ring. I looked at my phone, and I saw that it was my boss. I watched the display on the phone blink while I was thinking about whether to answer it or not.