19.4 目的状语从句
	表示目的状语的从句可以由that, so that, in order that, lest, for fear that, in case等词引导，例如： 　　 You must speak louder so that /in order that you can be heard by all. 　　 He wrote the name down for fear that(lest) he should forget it. 　　 Better take more clothes in case the weather is cold.