vervain

1. So you need vervain?
   你要马鞭草吗？
2. But if it's about the vervain
   但是如果是因为马鞭草的事
3. You know about vervain?
   你知道马鞭草？
4. Blue Vervain has been called a natural tranquilizer and is used as an antiperiodic for nervous problems.
   马鞭草是天然的镇静剂，用作神经系统抗疟之用。

noun

1. any of numerous tropical or subtropical American plants of the genus Verbena grown for their showy spikes of variously colored flowers

   Synonym:    verbena