His spare time learning has equipped him for a career as an accountant.

—— for a career 是 has equipped 的目的状语，as an accountant 是 career 的定语。

The army was equipped with up-to-date weapons.

—— with up-to-date weapons 是 was equipped 的方式状语。看主动结构：

equip the army with with up-to-date weapons （用最新式武器装备军队）