一个实数的平方总是正数______．
根据平方的非负性可得，一个实数的平方总是正数或0．
故答案为：或0．
附加题：已知y=x2+px+q，当x=1时，y的值为2；当x=-2时，y的值为2，求当x=-3时，y的值．
— Did his performance _________ you?
— No, I didn’t like his performing style.
A．appeal to
B．deal with
C．adapt to
D．make up
