Chlorine is a kind of high effective and widely used germicide.氯是一种高效的杀菌剂，用途十分广泛。YOULUJIN ( sodium Dichloroisocyanurate ) is a kind of high effective and widely used germicide and disinfectant.优氯净 ( 二氯异氰尿酸钠 ) 是一种广谱高效的杀菌、...
A recorder is often used in our English class.英语课堂上我们经常使用录音机.She conducted an English class for Chinese students.她给中国学生上英语课.Certainly, we always have some homework after an English class.当然, 我们上完一节英语课后,总要有家庭作业....