有甲、乙、丙、丁四个烧杯均盛100 mL水，现向四个烧杯中分别放入等质量的Na、

She always does very well in the English exams. But she can _____understand Englishradio programs.    [ ]

A. always      

B. hardly      

C. already            

D. easily

The room became ______ crowded after the desk was moved out.

A．a little

B．fewer

C．less

D．much

二氧化锡

图14-21所示结构，弯矩图形状正确的是（）。

A.

B. 

C. 

D.

周围血反应骨髓幼红细胞增生程度准确的指标是

A．血红蛋白和红细胞数

B．网织红细胞百分数

C．网织红细胞绝对数

D．出现有核红细胞

E．出现染色质小体