1. Used to indicate that something is possible or may be true, but you are not certain; to indicate that you are making a rough guess at a number or quantity, rather than stating it exactly. English = perhaps, maybe.
2. Used to link a number of alternatives, to give another alternative, or to introduce a comment which corrects or modifies something you have just said. English = or.
3. Used immediately next to a verb to mean it is possible that what you say is true, but you are not certain. English = may, might.