经常服用生鸡蛋容易导致人体缺乏的维生素是（）。
A.维生素C
B.硫胺素
C.生物素
D.钴胺素
参考答案：C
Read and write. 你知道下面节日的日期吗？把句子补充完整。
1. New Year's Day is .
2. Women's Day is .
3. Children's Day is .
4. Teachers' Day is .
5. National Day is .
6. Your birthday is .
___ century has just gone by and we’re now in a new century.
A．The twenty
B．The twentieth
C．Twenty
D．Twentieth
