X=(―a―7)÷2
根据题意得X>0,即
(―a―7)÷2>0
解得a<-7
即a<-7的所有实数
根据所给中文意思填空,补全下列各句(1)他们作为交换生在新加坡学习英语已经一年了。They have been learning English as ____ in Singapore____ a year.(2)你喜欢和什么样的人交朋友?What ____ of person do you like to make ____ with?(3)我现在最想做的事情是睡觉。Now all I ever ____ to do is ____ .(4)你作导游多久了?____ have you been a tour ____ ?(5)我们每天花一个小时做作业。It ____us an hour____ our____ .