合适于群组评论辩论的收集交换方法有（）。
A、电子邮件。
B、论坛。
C、博客。
D、及时聊天。
E、文件上传和下载（收集硬盘）。
参考答案：B, C, D
下列说法正确的是（ ）
A．有理数的绝对值一定是正数
B．一个负数的绝对值是它的相反数
C．如果两个数的绝对值相等，那么这两个数相等
D．如果一个数的绝对值是它本身，那么这个数是正数
用单词的适当形式填空。
1. I have a fever, and I must take a lot of ______ (medicine) every day.
2. It's ______ (importance) for us to look some new words up in our dictionary.
3. In traditional Chinese doctors' opinion, we need a ______ (balanced) of yin. and
yang to be healthy.
4. If we want to be healthy, we must eat a______ (balance) diet.
5. Our school lies in the ______ (west) part of Changchun city.
But my house is in the ______ (eastern) of the city.
