The young engineer sat down on a rock and rested his head in his hands. He would never get home; it was 36 . For weeks he had been 37 in the Northwest Canadian forest. Now there was a terrible 38 behind his eyes, and 39 of all, he had gone blind. Suddenly a man 40 out of the woods, an Indian who had been hunting in the area. Seeing the engineer's 41 , he caught a fish in a nearby 42 and fed the sick man the 43 of the fish and some flesh from its head. 44 within a few hours the engineer's pain was 45 . A day later he could 46 again, and the next day he had 47 recovered. When he returned home, the engineer told the 48 to Dr Price. 49 years later did it become a(n) 50 fact that this was just an everyday lifeguard doing its work. For what the engineer did, by eating fish eyes, was to 51 vitamin (维生素). Vitamin A's biggest job is to keep the eyes 52 . Without Vitamin A, people and animals get night blindness and other eye problems. Without Vitamin A, people can even be totally blind. Vitamin A helps to keep the skin in good 53 . A also helps 54 bones and teeth and has something to do with proper 55 of blood cells. 小题1: A.hopeless B.useless C.careless D.timeless 小题2: A.lost B.losing C.hunting D.working 小题3: A.disaster B.illness C.pain D.heat 小题4: A.good B.bad C.best D.worst 小题5: A.reached B.appeared C.hid D.watched 小题6: A.starvation B.trouble C.reality D.situation 小题7: A.pond B.stream C.place D.sea 小题8: A.tail B.skin C.eyes D.bone 小题9: A.Possibly B.Immediately C.Fortunately D.Surprisingly 小题10: A.gone B.shown C.settled D.disappeared 小题11: A.speak B.see C.walk D.work 小题12: A.completely B.naturally C.partly D.physically 小题13: A.news B.result C.secret D.story 小题14: A.Unless B.After C.Not until D.When 小题15: A.recognized B.accepted C.solved D.explained 小题16: A.keep B.bring C.take D.try 小题17: A.working B.rolling C.moving D.going 小题18: A.place B.order C.shape D.sense 小题19: A.from B.by C.about D.with 小题20: A.type B.growth C.choice D.size