staff用作名词，意思是员工、全体人员、全体职员。例句：The staff were very good 职员都很出色。10 staff were allocated to the task 10名员工被分配来完成这项任务。They are staffed by volunteers 它们的工作人员都是志愿者。staff用作名词、动词，意思是材料、原料、塞满。例句：I'd like some coffee, and I don't object to the powdered stuff if it's all you've got我想来点咖啡，如果你只有速溶的那种也可以。He grabbed my purse, opened it and stuffed it full, then gave it back to me 他抢过我的钱包，打开并塞满钱，然后还给了我。I could stuff myself with ten chocolate bars and half an hour later eat a big meal.我可以一口气吃10块巧克力，半小时后再吃一顿大餐。
Material: 材料, 在英文里一般指用作制造某样物件的东西 (we used some expensive materials to create this delicious dish)，也可指文件（如：The materials we prepared for the court inculded a cover letter, and .....)substance: 物质, 一般用于较专业的用语，指某特定物质（如：the immune response recognizes invading substances), 也可指烟、酒和毒品的统称（如：substance abuse can cause serious consequences.)stuff: 就是’东西‘的意思，比较口语化，如：I don't like stuff that smells like durian - 我不喜欢闻起来像榴莲的东西。
Candy00321
