助学目
标:
让学生掌握以下单词、词组和句子。
单词：imagine-various 16个（见词汇表）
词组: 1. 目前；现在 at present = at the moment = now
2. 变得越来越拥挤和受污染 become more and more crowded and polluted
3. 首先 first of all= firstly
4. 许多 large numbers of = a number of = many
5. 以…….速度 at a speed of …
