下列关于Oracle数据库系统的叙述中，哪个是不正确的?
下列关于Oracle体系结构的叙述中，不正确的是
"把查询sc表和更新sc表的grade列的权限授予用户user1"的正确SQL语句是______。
下列关于关系模式的码和外码的叙述中，哪一条是正确的?
He paid the boy $10 for washing ten windows,most of ____ hadn't been cleaned for at least a year.
What is a generally acknowledged as the most powerful advertising medium and reaches abroad spectrum of consumers. （）
Some customers requested us to _____ our price because they considered it too high.
Adults sometimes envy children who play all the time____they themselves have to work.rain orshine.
While I was waiting for her ,I killed time____looking in the show windows.
____, she led a life of complete seclusion.
航空货代具有( )身份。
Mario: Your beloved teacher has arrived here, Nina.
Nina: I______ she ______ until tomorrow.
我国海关机关规定，进口货物的收货人自运输工具申报进境之日起，超过（）时间未向海关申报的，其进口货物由海关提取依法变卖处理。
On which date are James and Alan going to meet?