meanings of when?

Question

does "when" have many meanings?
sometimes it means while,,,,,for example,when i talk, don't walk away(while i talk , don't go away,,,)

sometimes it means,,,,after,,,for example,,,when i read a book,i went to bed....(after i read a book, i went to bed,,)

sometimes it means,,before,,for example,,,turn off the lights when you go to bed,,(turn off the lights before you go to bed,,)

am i right???

Answer 1

Your 2nd example doesn't really make sence, "when" is not the best word there. If you take the other examples "when" really means "at the time". You don't want someone walking away at the time you are talking to them. You put out the lights at the time you go to bed. It can be slightly non-specific, but "while" is closer than "before" or "after". For example I turn off some of the lights before I get in bed and the last one after, so "while" is more accurate.

Answer 2

As usual Aiko you are astute in spotting oddities in the English language. In part the problem here is that yes "when" does have more than one meaning but also that most people in casual speech are not being very careful and rigorous in their choice of words. "When" gets used vaguely to indicate a relationship in time that may also involve a causal relationship (B is after A but B is also because of A).