第三人称单数
现在分词
过去式
过去分词
free of lice
He says the gas chambers were used only to de-louse corpses and objects.
BBC: Gas chambers did not exist - historian
英汉双解词典包含3185865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。