17.play by ear 随机应变,视情形而定 18.ring a bell 令人想起某件事,听起来耳熟 19.share a common outlook 有共同的观点 20.six of one and half-a-dozen of the other 半斤八两,没什么区别 21.stick around 在附近逗留或等待 22.stick with 继续做,坚持 23.straigh...