嘌呤核苷酸的抗代谢物是()
A.5-氟尿嘧啶(5-FU)
B.6-巯基嘌呤(6MP)
C.次黄嘌呤核苷酸(IMP)
D.β-丙氨酸
E.尿酸
参考答案:B
The girl is doing _____ homework. [ ]
A. his
B. hers
C. her
D. she's
万用表的实质是一个带有()的磁电式仪表。