I have one more question. I know that we often use would with present tense meaning the past, to point out that activity was often repeated. And here comes my sentence: Again, the talk is about a teacher who had a habit of discriminatig girls. "When a boy asked question he smiled and asked for his answer" can't I say" When a boy asked a question he would smile and (would) ask for his answer"?. I guess I can not say "When a boy would ask a question" but can't I use would in other parts to point out that it happened always?
You could say 'when a boy would ask', but it would make it a bit unclear as it could mean that one particular boy repeatedly asked questions, so if you say 'a boy', then it works better without 'would' for me.