下面哪些是产生线路坑洼的原因（）。
A、轨缝过大
B、钢轨拱腰
C、低接头
D、轨面有擦伤
E、捣固不良，软硬不均，空吊板多
参考答案：A, B, C, D
用所给单词的适当形式填空。
1. Please write to _____ (I) soon, Linda.
2. Here is a card with our _____ (good) wishes for your birthday.
3. His brother usually _____ (get) to school at seven-fifteen.
4. We love _____ (listen) to our math teacher.
5. Linda's aunt _____ (brush) teeth after dinner.
不宜与制酸药合用的药物是
A．磺胺甲噁唑
B．氧氟沙星
C．甲氧苄啶
D．呋喃唑酮
E．呋喃妥因
