来自世界不同地方的六位学生在美国相遇。他们都是交换学生，到美国大学就读一个学期，学习英语，了解美国文化，同时修专业课程。英语“日常会话” (Everyday Conversations)系列围绕这六位学生在美国的经历展开。这套材料适于中级或中级以上英语水平的学生使用。
两个学生（Peter and Akinyi）谈清洁安全饮水的重要。
Peter: Is that a straw?
Akinyi: Yes. Isn’t it great? This is a solution to water scarcity.
Peter: You’re starting to sound a bit like Lee. Are you studying water scarcity in a class? And how is a straw the solution?
Akinyi: I’m studying the business model of one company that creates these filter straws. Believe it or not, this straw is a portable water purifier.
Peter: Is there really a large need for a water purifier to be portable?
Akinyi: Definitely. We all know that clean and safe water is essential to healthy living. But lack of clean water can affect the education of many children in the world.
Peter: Really? How?
Akinyi: Well, for example, students might get sick from drinking unsafe water and miss school.
Peter: And if students can carry filter straws, then they can always drink safe water?
Akinyi: Exactly. The straws have iodine, charcoal and filters – these combine to reduce harmful particles and remove bacteria. And they last up to a year!
Peter: Wow. That seems like a great solution for people without access to clean and safe drinking water.
让我们来学习一些词语（也可阅读英文解释）：
A straw：喝饮料用的吸管
Water scarcity ：缺水，也可指缺少清洁饮水
A business model ：商务模型，通常包含宗旨、目标以及达标步骤或举措
A filter ：过滤装置，用于过滤清除水或空气中的有害物质。在这个对话中，过滤吸管是用于饮水。吸管带有过滤装置，可以将有害细菌（可致病的微生物）和颗粒物质从水中去除。
形容某件东西 portable，是指它可以被携带，即便携式的。
To purify 的意思是净化。A water purifier是生水净化器 。
Essential: 必要的，极其重要的，绝对需要的
Iodine：碘。它有杀菌功能，可被用来净化水。
Charcoal ：木炭。它可清除水中有害物质，并改善水的味道，因此也被用来净化水。
Bacteria ：细菌，（复数bacterium）
有兴趣听更多英语对话吗？请浏览“英语学习”专题网页。
American English 网站提供可供英语学生和教师免费使用的多种英语资源。American English Facebook网页提供每天更新的英语学习资料。
“日常会话”由美国国务院教育与文化事务局英语语言项目处（Office of English Language Programs, Bureau of Educational and Cultural Affairs）资深项目官员海蒂·豪兰（Heidi Howland）编写。
