Has he _____ you to his birthday party?[ ]
A. ask
B. invited
C. wants
D. have
答案:B
血站最早采用的是哪种质量管理体系()。
A.IS09000
B.IS017025
C.IS015189
D.GMP
E.《临床输血技术规范》
— You look unhappy, my son?
— I'm wondering how long it'll be we come to China again. [ ]
A. since
B. when
C. before
D. after