了防治杂散电流，铠装电缆和金属管路要定期（），不回电轨道和回电轨道要加设（），并经常维护。
参考答案：涂绝缘漆；绝缘
用所给词的适当形式填空。
1. My father wants ________ (go) Canada next year.
2. Jenny usually ________ (watch) TV at night.
3. He hopes ________ (meet) Mr. Jackson in Hong Kong.
4. Be quiet! The teacher ________ (come).
5. A good ________ (begin) makes a good ending,
6. Do elephants like eating ________ (leaf)?
7. There ________ (be) some bread in the bag.
8. Why ________ your brother ________ (like) playing basketball?
9. They are very ________ (friend).
10. There ________ (be) some bread n the bag.
在食品中加入了与原有食品（）、颜色相似的杂物，属掺杂食品。
A、形状
B、价格
C、口味
D、名称
