单选题 You're ______ your time trying to persuade him; he'll never join us.
【正确答案】 B
【答案解析】[精解] waste time doing sth. 意为“浪费时间做某事”；spend time doing sth. 意为“花费时间做某事”，所提供的情境he'll never join us说明“劝说他参加是浪费时间”。故正确答案选B。