用所给单词的适当形式填空。

1．Look! One of the ______________ (policewoman) is running after a man.

2．Some children are playing volleyball, and others ______________ (sit) on the beach.

3．It's snowing hard. It's a ______________ (snow) day.

4．They are ______________ (Canada), so they can speak English and French.

5．Lily is very ______________ (excite) because she wears a nice dress.

婴儿佝偻病发病的主要原因是()

A．甲状旁腺功能不全

B．维生素D缺乏

C．钙缺乏

D．食物中钙磷比例不当

E．婴儿生长发育快