– I think teenagers should be allowed to meet internet friends alone.– ________. It's not safe enough.
A：I disagree
B：I think so
C：I agree
If you buy ________ MP4 player in our store, you can get a watch for ________ free.
把字换一个偏旁，成为本课的生字。
坡——____ 球——____ 谎——____
如果a为任意实数，下列根式一定有意义的是（ ）
