关于胎盘生乳素,下列哪项正确:
A.由细胞滋养细胞产生
B.是糖蛋白激素
C.分子量约为3.5万
D.可以在孕妇血中测出
E.母血胎盘生乳素值与胎盘大小呈反比
参考答案:D
Your friend Lili used to play the piano, _______? [ ]
A. used she
B. doesn't she
C. didn't she
D. did she
FCA、CIP、CPT三种贸易术语,就卖方要承担的义务而言,FCA最小,CPT其次,CIP最大。 ( )