to speak one's mind	honestly say how you really feel
to spread like wildfire	spreads very quickly
straight from the horse's mouth	hear sth from a person who has direct knowledge
to stretch the truth	to make sth sound better than it is
to take sth with a grain of salt	to be skeptical about the information you hear
to be like talking to a brick wall	talking to someone who is not listening or saying anything
to beat a dead horse	waste time on sth that is never going to happen/ continue talking about sth that has already been
to beat around the bush	to avoid or delay talking about a subject directly - owijac w bawelne
beside the point	sth is irrelevant or off topic
to bite one's tongue	stop yourself from saying sth that will probably get you in trouble
to butter someone up	flatter someone because you want sth from him
to talk sth over	you discuss sth with someone in order to get their opinion before you make a decision
to talk sth/sb up	speak positively about that person or thing in order to influence other people's opinion
(spread by) word of mouth	poczta pantoflowa - przekaz ustny