浓缩机的型号是()。
A.TLL-900A.
B.HMD.A.-7
C.NXZ-20
参考答案:C
My watch doesn't work. I must have it ______.[ ]
A. repaired
B. repairs
C. repair
D. repairing
若关于x的方程5x-2a+4=3x的解是负数,则a的取值范围是______.