verazine

例句：

1. 1. The doctor prescribed a vitamin B12 supplement for her.
   医生给她开了一种维生素B12补充剂。
2. 2.Vitamin B12 deficiency can lead to fatigue and weakness.
   维生素B12缺乏会导致疲劳和虚弱。
3. 3.She took the medication as directed and felt better after a few days.
   她按照指示服用了药物，几天后感觉好多了。