概括：内容选自老托福听力，是练习托福听力的绝佳材料。


Hints:
Experiments
Activities
Chapter One
Before we start our first lab, I'd like to tell you a little bit about the workbook we'll be using. The first thing I'd like to point out is that the workbook contains a very large amount of material - far more than you could ever handle in a single semester. What you're supposed to do is choose the experiments and activities that you want to do within a certain framework, of course. Part of my job is to help you make your choices. Next, I'd like to mention that in each workbook chapter, there are usually two subsections - the first is called "Experiments" and the second is called "Activities". In the "Experiments" section, the workbook gives full instructions for all the experiments, including alternate procedures. Choose the procedure you wish, there's plenty of equipment available. In the "Activities" section, you will find suggestions for projects that you can do on your own time. You'll see that there are usually no detailed instructions for the activities, you're supposed to do them your own way. If there are no questions, let's turn to Chapter One now.