feel free
　　用：允许别人做某事，让他不要感到拘束时的用语。
　　意：你请便！你随便！别客气！别拘束！
　　例，Just feel free to come and go when you like.
　　您来去自由，请别构束。
　　A: May I use your bathroom?
　　我能用你的卫生间吗？
　　B: Feel free!
　　请便！
　　I must (I've got to) fly.
　　意：我得走了；我必须走了（因有其他要紧的事）
　　例：I wish we could have finished the discussion, but I must fly.
　　真希望我们能讨论完，可是我得马上走了。
　　I've got to fly-a friend is waiting for me in his car outside.
　　我得走了，有个朋友在外面车子里等我呢！
　　a feather in his( her)cap
　　意：值得夸耀（骄傲）的事；卓越的成就；荣誉的标志
　　例：If he clinches this deal, that'll really be the feather in his cap!
　　如果他能做成这笔交易，那才真正值得他骄傲呢！
　　It was a real feather in his cap for the new teacher when he was made head of the English department.
　　被任命为英语系主任，这对那位新教师来说真是件值得骄傲的事。

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