【正确答案】Mode of discourse mainly refers to the means of communication. It is concemed with "how" communication is carried out: oral, written, etc.

【答案解析】[解析] 本题考查的是考生对话语方式的理解。话语方式是指话语的交际渠道和方式，即交际是通过何种方式进行的，分为口语、书面语等。