16. tool 工具
用于tool for doing sth，意为“做某事的工具”。如：
This is a tool for opening tins. 这是一个开罐头的工具。
A corkscrew is a tool for opening bottles. 螺丝刀是用来开启瓶塞的工具。
有时用于引申义。如：
A good education is a necessary tool for succeeding. 良好的教育是成功的必要手段。
Words are essential tools for formulating and communicating thoughts. 语言是表达思想和交流思想的重要工作。
17. vocation 禀性，才能
用于vocation for doing sth，意为“做某事的禀性（才能）”。如：
He has little vocation for teaching. 他不是教书的材料。
She has a vocation for looking after the sick. 她有照顾病人的本领。
You should become a welfare worker; you have a vocation for helping people. 你应该去从事社会福利工作，因为你有乐于助人的禀性。