题型：判断题 单句改错1. My uncle has become a Party member for ten years.2. Have you gone to the Great wall?3. -Who likes maths in your class? -None.4. Mr. Zhang reached two hour ago.________________________________________________________________________________ 查看答案
题型：判断题 若关系R、S如下图所示，π1,3,7(σ3＜6(R×S))= (30) ，且结果集的元组列数和元组个数分别为 (31) ，R÷S= (32) 。 A．供应商所在地in’%西安%’B．供应商所在地like’西安%’C．供应商所在地like’%西安%’D．供应商所在地like’西安%’ 查看答案