191．on a diet 吃某种特殊饮食，节食
192．differ from……in 与……的区别于……
193．in difficulties…… 有困难，处境困难，
194．discharge sb. (from)……for (=dismiss sb. from a job for) 因……解雇，开除
195．fall back (=retreat， turn back) 撤退；in disorder慌乱地，狼狈不堪
196．on display (＝being shown publicly) 陈列
197．dispose of (=get rid of， throw away) 处理掉
198．beyond dispute 不容争议的，无可争议
199．in dispute 在争议中
200．in the distance 在远处．make out 辩认出
201．(be) distinct from ( = be different from) 与……截然不同
202．distinguish between (=make or recognize differences) 辨别
203．distinguish……from 把……与……区别开
204．do away with (=get rid of; abolish; discard eliminate ) 除去，废除，取消； do away with (=kill) 杀掉，镇压
205．have……to do with 与……有关系
206．without doubt (=undoubtedly) 无可置疑地
207．in doubt (=in a condition of uncertainty ) 对……表示疑惑
208．be due to 是由于
209．come off duty 下班
210．go on duty 上班
211．be on duty 值班，值日，在上班时
212．be in duty bound to (do) (=be required by ones 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 ones 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 (ones) 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
221.economize on （=save sth. instead of being wasteful） 节省
222.have an effect on 对……有影响
223.be in effect （=be in operation） 有效
224.go into effect 生效。（近：come into effect; take effect; be brought into effect）
225.in effect （=in fact， really） 实际上