近视产生的原因可能是（）
A.眼球前后径过短
B.眼球前后径过长
C.折光力过强
D.折光力过弱
E.晶状体弹性减弱
参考答案：B, C
根据首字母及句意补全单词
1. She d_____ to take a long vacation.
2.I have to b_____ my little sister this afternoon.
3. Amy is an active girl .She is o_____.
4. They are twin sisters. They also have some differences, t_____.
5. Some students exercise once or t_____ a week.
天麻钩藤饮的组成中含有的药物是（）
A．钩藤、川牛膝
B．钩藤、生龙骨
C．钩藤、川贝母
D．钩藤、生牡蛎
E．钩藤、生龟甲
