_______ is no need to worry if you have never skied before.
A.It
B.That
C.There
D.This
答案:C
小儿体重在1~10岁时每年增长约()。
A.1kg
B.2kg
C.3kg
D.4kg
E.5kg
骨髓中不出现幼红细胞的疾病()
A.急性失血后贫血
B.溶血性贫血
C.骨髓纤维化
D.低增生性白血病
E.再障