人工制品如农药的使用，可达到增产防病的目的，对环境的影响是（）.
A.不影响环境
B.环境隐患和不安全因素增加
C.无环境隐患
D.对人安全
参考答案：B
将小麦种子切开，滴加少量碘液，小麦种子变蓝，这说明种子中含（ ）
A．水分
B．蛋白质
C．淀粉
D．脂肪
请你用所给单词的适当形式填空。
1.Teenagers should ________ to choose their own clothes. (allow)
2.I think it's wrong to get our ears _________ when we are at school. (pierce)
3.Have you made a ________ to buy an MP4? (decide)
4.You must pay attention to your _________. (pronounce)
5.I am very ________ of my head teacher. (terrify)
