单词：potash dichromate
重铬酸钾
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The little splints of wood which we call matches are made out of deal or pine wood which has been soaked in melted paraffin wax to make it burn more easily. 这种被我们称之为火柴的薄木片由欧洲赤松（松树）制成, 在液体的石蜡
发表于:2018-12-18 / 阅读(38) / 评论(0)
英国学生科学读本
英国学生科学读本
This is the VOA Special English Development Report. One of the best ways to protect yourself and other people from getting sick is to wash your hands with soap. To make soap, you need three main things: oil, water and lye. The oil can come from anim
发表于:2019-01-11 / 阅读(69) / 评论(0)
VOA慢速英语2008年（十二）月
VOA慢速英语2008年（十二）月