1. To speak words. English = say.
2. To use spoken words, written words or signs to communicate something to someone else. English = say, tell.
3. To use spoken words, written words or signs to briefly talk about something to someone else (usually when the main reason for the communication is another piece of information). English = mention.
4. To say something that gives your opinion of something or which gives an explanation of it. English = comment.
5. To say that something is the case in a firm, deliberate way. English = declare.