数据管理技术的发展经历了如下三个阶段:人工管理阶段、文件系统阶段和【 】系统阶段。
参考答案:数据库
选择与画线部分意义相同或相近的选项。
1. The dog is kind of dangerous.
A. a kind of
B. a little
C. a little of
D. a bit of
2. Jim looks like his father.
A. is like
B. likes
C. looks at
D. is liking
3. There is nobody on the street.
A. no one
B. anybody
C. no man
D. not anybody
4. I would like to visit a friend this afternoon.
A. think
B. hope
C. want
D. go
5. My brother's favorite food is beef. What about you?
A. What are
B. How are
C. How about
D. What for
森林生态系统的主要特征。