211. be on duty 值班, 值日, 在上班时

　　212. be in duty bound to (do) (=be required by one’s job or esp. by conscience) 有义务(做)

　　213. be eager for 想得到, 盼望

　　214. by ear (=play music from memory without having seen it printed) 凭记忆,不看乐谱

　　215. have an ear for (=have keen recognition of sounds esp. in music and language)对..有鉴赏力

　　216. a word in one’s ear 私房话, 秘密话

　　217. on earth 究竟, 到底, 全然

　　218. with ease ( = easily) 容易, 不费力

　　219. at (one’s) ease ( = without worry or nervousness) 自在,不拘束

　　220. put sb. at his her ease (=free sb. from worry or nervousness)使某人感到无拘束