从助动词is 和选项可看出,此处是被动语态,即 recover 和 restore 都是及物动词.这两个词都有恢复健康的含义,但是有区别,recover 指使自己恢复到正常的状态,restore 指使自己或事物回复到原来的状态,因此二者的用法也不同,recover 有及物和不及物两种用法,而restore 只有及物一种用法.如表示“某人完全痊愈了”,就可以有如下的几种说法：
He has completely recovered (from illness).——不及物
He recovers himself (from illness).——及物,主动语态
— Heis recovered (from illness).——及物,被动语态
He restores himself (to health).主动语态,宾语为反身代词
— He isrestored (to health).被动语态
He restores his health (to a previous condition).主动语态,宾语为事物
— Hishealth is restores (to a previous condition).被动语态
可见,上述例句中只有最后一句与本题一样.
【翻译】一个月的治疗以后,他已经完全痊愈了（他的健康状况已经一如既往了）.