One's speech portrays one's character. It is in one's manner of communication that one can either win hearts or create hatred. By a simple and pure hearted conversation, it is so easy to gain the comfort and homeliness of the other party instead of asking rhetoric spiteful questions.
What kind of sadistic pleasure can anyone achieve by speaking spitefully and with ill intent? Is it not human decency to be pleasant to one and all, and to relate to other human beings' feelings and thoughts? What happiness can one derive by putting down others?
Knowing what to speak, when to speak and how to speak will go a long way in leading a better Life. A conversation, in which both the parties feel honoured to speak, automatically opens out heretofore never ventured avenues and strengthens the bond.
If it is not possible to be nice and pleasant, then the least one should do is just keep quiet. Silence speaks a lot more than one's actions.