Face–to–face conversation is a two–way process. You speak to me, I reply to you and so on. Two–way (1)_____ depends on having a coding system that is understood by both sender and (2)_____ , and an agreed convention about signaling the beginning and end of the message. In speech, the coding system is the language like English or Spanish; the convention that one person speaks at a time may seem too obvious to mention. In fact, the signals (3)_____ in conversation and meetings are often (4)_____ . For example, lowering the pitch of the voice may mean the end of a sentence, a sharp intake of breath may signal the desire to interrupt, catching the chairman’s eye may indicate the desire to speak in a formal setting like a debate, a clenched fist may indicate anger. When (5)_____ possible, more formal signals may be needed.