I want to ask about whether sourness or sweetness that comes up to one’s throat without reaching the mouth breaks one’s fasting or not. After I have the predawn meal and go to bed, I feel like something comes up to my throat. Does this break my fast?

If this sour substance does not reach the throat, it is nothing. If one involuntarily vomits, there will be nothing upon him. But if he intentionally vomits, he will have to make the day up.
It is just that one sometimes feels of something sour which he has no control over.
He is not obliged to do anything, if he has no control over it and nothing comes out.