I have _____ the book for three weeks. [ ]
A. lent
B. borrowed
C. bought
D. kept
答案:D
磁石的主治病证()
A.心神不宁
B.心悸失眠
C.肝阳上亢
D.头晕目眩
E.肾虚喘促
《卫生注册证书》有效期届满时,如果该企业的产品一直无质量问题,其有效期将自动延长。 ( )