数据库系统的核心是A．数据模型 B．数据库管理系统 C．软件工具 D．数据库 发布时间：2017-06-15 21:45 │ 来源：www.tikuol.com 题型：单项选择题 问题： 数据库系统的核心是A．数据模型B．数据库管理系统C．软件工具D．数据库
题型：单项选择题 单词分类。A. frustrating B. do more exercises C. listening to tapes D. excited E. boring F. asking questions G. bored H. watch movies I. frustrated J. getting an English tutor1. The game is so _____ that I can't stand it.2. After having a Chinese class, I felt _____.3. I'd like to learn English by _____. Do you think learning by surfing the Internet is good or bad? Why?________________________________________________ 查看答案