笼养蛋鸡疲劳综合征又称为( )。A．观星症 B．锰缺乏症 C．骨短粗症 D．趾爪蜷
题型：单项选择题
问题：
笼养蛋鸡疲劳综合征又称为( )。
A．观星症
B．锰缺乏症
C．骨短粗症
D．趾爪蜷曲症
E．骨质疏松症
题型：单项选择题
根据短文内容，用方框中所给单词的适当形式填空。每词限用一次。
Nowadays, we are paying more attention to our students’ safety in our country. But what do other countries do to keep students safe?
In Japan, earthquake drills (演练) are held once a month. They 小题1: students safety tips during an earthquake. The training 小题2: students escape from earthquake-stricken areas. In Australia, most students take first-aid courses at school. They learn basic first-aid 小题3: in the class, such as, how to use the emergency (紧急) number for an ambulance (救护车) and what to do 小题4: someone is hurt. Most US school buildings have fire escapes. They are told to get to the fire escape through a fire exit door or a window. It is not a good idea to jump out of the window from 小题5: than two floors because they may get injured.