Ⅰ.单句填空
1.They are determined (recycle) their garbage because they care about the environment.
答案to recycle
2.The research (lack) solid evidence,and therefore,its conclusions are doubtful.
答案lacks
3.Can you tell the pupils why ships are able (float) on the sea?
答案to float
4.I haven’t seen Sara since she was a little girl,and she has changed recognition.
答案beyond
5.Only when agriculture is fully developed can industry have (sufficiency) materials and markets.
答案sufficient
