这栋建筑被宣布不适合人类居住。

The building was declared ___unfit for human habitation.

汽车也排放一氧化碳，使空气不适合呼吸。

Cars also emit carbon monoxide and make the air ___unfit to breathe.

他糟糕的健康状况使他不适合服兵役。

His poor health made him ___unfit for military service.