I only really want to comment on the 3rd question, re see, look and watch.

Apart from fixed, conventional, uses and very situation specific examples, as per Dave Rattigan's reply, the main distinction drawn in EFL generally is as follows:

1. See - focusses on the result of an act of observation, on (some sort of) information being taken in and processed. e.g.
A: "Did you see that?"
B: "What?"
A: "The man with the gun."
(Meaning: You should be scared / run.)

2. 'Look at' and 'watch' are generally paired in that they both focus on the act / process of observation, rather than the result:

a. Look at - generally used to refer to static
things / objects, etc. e.g 'look at a picture', etc.

b. watch - tends to be used for more dynamic
situations or where the focus of attention is the
action rather than the object, so:
i. 'watch TV' - i.e. focussing one's attention on
the movement, action, etc, on the screen,
rather than on the control buttons, special
features, etc as one might when choosing a
TV ("We *saw* a really nice new Sony in the
shop on Saturday. Bit expensive, though.").
ii. 'watch the match' - one watches the players'
movements, etc.

c. where this becomes a little trickier is in cases where one could use either. Contrast:
i. 'look at the girl sitting outside the cafe'
("Doesn't she have a cool hairdo!") and
ii. 'watch the girl sitting outside the cafe'
("She's passing a suspicious package to a
man in a long raincoat and sunglasses.")

d. An even trickier one, however, is 'watch the match' and 'see the match', where there is very little distinction and one would probably be left having to say that the distinction was simply one of result vs. process. I.e. if you *watch* the match, you're more interested in the enjoyment from watching it, whereas if you *see* the match, you're probably more interested in the result.

Contrast:

A: "Did you watch the match on Saturday?"
B: "Yes, I went to the (insert name of bar) with (insert name of friend). We had a great time."

and

A: "Did you see the match on Saturday?"
B: "Yes, I was excellent! We thrashed them this time!"

e. note also that 'see' doesn't tend to occur in progressive / continuous tenses (apart from to see someone as in the case of boyfriend girlfriend, etc: "I'm seeing this really nice girl at the moment.") - which is consistent with it being focussed on result rather that process. 'Look at' and 'watch' are possible in both continuous and simple tenses.