see a man about a dog used euphemistically when leaving to go to the lavatory or if you do not wish to disclose the nature of the errand you are about to undertake. humorous
英语词组固定搭配大全包含15956条英汉双解词组,基本涵盖了全部常用英文词组、短语的翻译及用法,是英语学习的有利工具。