变电站(生产厂房)外墙、竖井等处固定的爬梯,应(),并设护笼,高百米以上的爬梯,中间应设有休息的平台,并应定期进行检查和维护
A、便于攀爬
B、整洁美观
C、牢固可靠
参考答案:C
单词拼写。
1. I soon noticed his ________from school.
我不久就注意到他没来上学.
2. He _________to the teacher for being late for school last week.
由于上学迟到他向老师道歉了.
3. I found the temptation to miss the class too hard to ________.
我抵挡不住逃课的诱惑.
4. Don't _________to ask us for help especially when you are in trouble.
不要犹豫向我们寻求帮助尤其是你有麻烦的时候.
5. Citizens are __________to the government to protect environment.
市民们正在呼吁政府保护环境.
6. Have you _________yourself to the life of the high school?
你调整你自己适应高中生活了吗?
7. It is __________of you to help me when I am in trouble.
在我困难的时候你帮助我,你真体贴周到.
8. His parents ________him for his mistakes last week.
他的父母原谅了他的错误.
9. He was ___________because of not passing the exam.
他由于没有通过考试而感到沮丧.
10. The boy often _________what others do.
这位小男孩经常不理会别人所做的事情.
数据库管理系统能实现对数据库中数据的查询、插入、修改和删除,这类功能称为
A.数据定义功能
B.数据管理功能
C.数据操纵功能
D.数据控制功能