Jonny, I can't believe how much you have changed! You _____ at least one foot!   [ ]

A. grow            

B. grew          

C. have grown        

D. are growing

判断骨髓增生程度的主要标准是（）

A.粒细胞/幼稚细胞

B.有核细胞/粒细胞

C.成熟红细胞/有核细胞

D.粒细胞/成熟红细胞

E.成熟红细胞/粒细胞