CHAPTER PARTS OF SPEECH ∨铅是用在铅笔里的那种金属。 Lead is the very metal used in pencils. a pencill 压力的增加总是引起体积的减小。 An increase of /in pressure always causes a decrease of /in volume. a volume decrease]铅是用在铅笔里的那种金属。 CHAPTER I PARTS OF SPEECH Lead is the very metal used in pencils. [ a pencil] 压力的增加总是引起体积的减小。 An increase of /in pressure always causes a decrease of /in volume. [a volume decrease]