q:关于x的不等式x2+x+a>0恒成立.
若p或q为真命题,¬p或¬q也为真命题,求实数a的取值范围.
万德的同学上学通常都比乌鲁木齐的小朋友要早,这是由于( )
Lucy didn't feel well last week. She ____ all day and all night.