99色精品-9色在线-99色在线-99色视频 国产欧美日产一区二区三区_亚洲精品亚洲人成在线观看_四虎在线精品永久观看_免费一级a一片久久精

單項(xiàng)選擇題

他們應(yīng)該明白不同報(bào)警信號的意義。()

A. They should be clear about all fire-fighting equipment..
B. They should be understood about the meaning of the different alarm signals.
C. They should be clear about all life-saving equipment.
D. They should be clear about the meaning of the different alarm signals.

微信掃碼免費(fèi)搜題