burn down
(of a fire) burn less brightly or strongly (指火)渐渐烧完; 火力减弱
The room grew colder as the fire burnt down. 随著炉火逐渐减弱, 房间越来越冷. burn (sth) down (cause sth to) be destroyed to the foundations by fire (将某物)焚为平地, 烧得精光
The house burnt down in half an hour. 那所房子在半小时之内就被焚为平地.
Don´t leave the gas on you might burn the house down. 别忘了关煤气炉--不然会把房子烧掉的.