精选优质文档-倾情为你奉上实战讲稿Speaking实战讲稿Step 1: Leading in: by discussion. Hi, boys and girls. We are now living in a highly developed world, with advanced culture and highly developed civilizations. But have you ever thought what are the base of all the culture and civilizations? Oh, yes, they are based on those which were created by our great, great grandfathers lived a long, long time ago. No one exactly knows what they lived on, what were their housing and home decoration conditions, what