若关于x的一元一次方程x-m+2=0的解是负数,则m的取值范围是( )
We have a job ________ you ______ a waiter.
读一读,选择正确的答案,将字母代号写入前面的括号内。
①Is he young?____ A. She's my sister.
②Is that a boy? ____ B. No, she's a girl.
③Who's she? ____ C. Yes, he is.
若﹣3xmy3与2x4yn是同类项,则mn=____.