Vitamins(维生素)are a discovery of this century．A hundred years 　　1　　, no one knew anything 　　2　　 them．The vitamins are 　　3　　 by letters of alphabet．Vitamin A 　　4　　 by the eyes．There is Vitamin A in milk, butter and green vegetables．It 　　5　　 by the body．

　　Vitamin B must be supplied(提供)　　6　　 by some of our food．The skins 　　7　　 grains of all sorts have Vitamin B in them．

　　Vitamin C is very important 　　8　　 the body．Without it 　　9　　 teeth will become loose and their arms and legs become weak．Oranges and tomatoes 　　10　　 Vitamin C in them．

　　There are other vitamins．But these A, B, C are the most important．

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