There was a look of unalloyed pleasure on the man's face.那个人脸上洋溢着纯粹的快乐。
an occasion of unalloyed joy一个欢乐十足的场合
英汉双解词典包含368430条英汉词条，基本涵盖了全部常用单词的翻译及用法，是英语学习的有利工具。