Using Natural Building Materials

00:00:00,620Section four. You will hear a lecturer talking to environmental science students about building methods using natural materials. 00:00:11,160First, you have some time to look at questions thirty-one to forty on page seven. 00:01:06,760Now listen carefully and answer questions thirty-one to forty. 00:01:13,160There is growing interest in building structures using natural materials these days. I'll begin this lecture by looking at how some of these materials work, some advantages and p...