Visual FoxPro系统为用户提供了29个基类，这些基类又可以分为2种类型，即：容器类和 【20】 。
参考答案：控件类
用所给单词的适当形式完成句子。
1. More and more _____ (danger) animals need to be protected by us.
2. Don't worry. We _____ (support) you when you have the match.
3. _____ (recycle) paper to save trees is very important.
4. Your house is very old. It should be _____ (pull) down.
5. Why are you _____ (wear) a coat in such hot day?
法定历史保护建筑的保护内容主要是( )。
A．建筑物和所在地区及城市
B．建筑物实体和环境
C．建筑物内部及立面外观
D．建筑物结构和构造
