单项选择题
---This digital camera is really cheap! ---The ______ the better. I’m short of money, you see. A. cheap B. cheaper
问答题 C1=～P∨Q∨R，C2=P∨S，C1、C2的归结式为( )。____
单项选择题 hiss是哪种动物发出的声音？A. snakeB. sheepC. pigeon
单项选择题 积分( )
