whereby

adv. /werˈbaɪ/ C1

借此；凭此

By which, or because of which something happens.

仙境例句

The Caterpillar told her of a way whereby she could grow taller or shorter as she liked.

毛毛虫告诉她一个办法，靠这个办法，她想变高就变高，想变矮就变矮。