西非大草原上的人们驯养了马，后来他们强大的骑兵部队使他们得以建立起庞大的帝国。

Horses were adopted by peoples of the West African savannah, and later their powerful cavalry forces allowed them to carve out large empires.

youdao

骑兵部队必须立即补充新马。

The cavalry must immediately replenish the new horse.

youdao

没有马镫，马和骑手在力量上是独立的实体；长枪可以从马背上使用，但只能通过投掷或刺杀，骑兵只能获得高度和机动性。

Without stirrups horse and rider are, in terms of force, separate entities; lances can be used from horseback, but only by throwing or stabbing, and mounted warriors gain only height and mobility.

youdao