I have two questions here:
- To which action we can use Stop + gerund?
- And to which action we can use Stop + to + infinitive?
- Notice the difference between stop doing something and stop to do something - We stopped taking pictures means ‘We were no longer taking pictures.’;We stopped to take pictures means ‘We stopped what we were doing so that we could start taking pictures.’
(Oxford Learner's Dictionary)
He stopped to look at the window shop. (He was walking and he stopped in order to look at the window shop)
He stopped looking at the windows shop. (He was looking at the window shop and decided not to look at it any longer)
We use the -ing form after stop to indicate that an action or event is no longer continuing:
It’s stopped raining. Let’s go for a walk. (It was raining, but not any more.)
We use the to-infinitive after stop to indicate that someone stops doing something in order to do something else:
On the way to London, we stopped to look at an old castle. (We were travelling, then we stopped our journey in order to look at the castle.)