以（）等两层材料所组合而成的导电层便称为Polycide。
A.单晶硅
B.多晶硅
C.硅化金属
D.二氧化硅
E.氮化硅
参考答案：B, C
用所给单词的适当形式完成下列句子。
1. How many (season) do you know?
2. On a holiday, people (not work).
3. Danny (walk) to school yesterday.
4. We are (put) Christmas things on the tree now.
5. Li Ming teaches (I) to learn Chinese.
起重吊运指挥信号（GB5082～85）不适用于（）、载入电梯设备。
A、矿井提升设备
B、门式起重机
C、铁路起重机
D、桅杆起重机
