阅读短文，掌握其大意，然后从A.B、C、D中选出可以填入空白处的最佳选项。
A boy guarded the barrels (木桶) in his father's winery (葡萄酒厂). Every morning, his father gave him a 1 of brushing the barrels and putting them in order, but the wind blew the barrels here and there overnight.
The boy was so 2 that he wrote a letter to the wind, "Please don't blow down my barrels." After seeing that, his father asked the boy with a smile, "Can the wind read your 3 ?" The little boy said, "I don't know. I have no 4 but to make this request (请求)."
The next morning, when the little boy ran to 5 the barrels, he found that the barrels were blown here and there again. The little boy felt very unhappy and cried. His father came and said 6 , "Son, don't be sad. We may have no way to deal with the 7 , but we may have ways for you, so we can have our own ways to 8 the wind." Then the little boy 9 his tears and thought over and over. Finally, he thought of an idea. He filled the 10 barrels with water. After that, he went home worriedly.
The third morning, the little boy 11 his clothes in a hurry and ran out. He was 12 to find the barrels were placed in good order. The little boy smiled happily and told his father, "It's a very 13 way, that is, to make the barrels heavier." The little boy's father smiled and 14 his head.
We can't change many things in the world, but we can change ourselves. To add you the 15 is the only way not to be knocked over.
