【题目】If the house is ____ fire, _____ where is the nearest exit.
A.in; find
B.on; find out
C.catches; find
D.on; find

【答案】B
【解析】考查固定词组。on fire着火；find找到（找的结果），find out查出，弄清楚。句意：如果房子着火，找到最近的出口。故选B。