溴化锂吸收式制冷机组运行时出现结晶现象,其原因可能是()。
A、环境温度太高
B、环境温度太低
C、系统漏入空气
参考答案:C
Read and choose. (根据句子内容选出答案)
1. It's an animal. It likes to catch the mouse. It is a ____.[ ]
A. dog
B. cat
C. tiger
2. It's a kind of colours. The tree always have it. It is _____.[ ]
A. pink
B. white
C. green
3. It's a room. When you get tired you can sleep there. It is a _____.[ ]
A. bathroom
B. kitchen
C. bedroom
4. It's a kind of food. The rabbit likes it very much. It is a _____.[ ]
A. carrot
B. beef
C. bread
5. Winter is very cold. We can wear _____.[ ]
A. shirt
B. sweater
C. shorts
光纤宽带的入户安装调测时间要小于60分钟。