题干

已知在直角坐标系xOy中,曲线C1{x=3cosθ+sinθy=3sinθcosθ (θ为参数),在以平面直角坐标系的原点O为极点,x轴的正半轴为极轴,取相同单位长度的极坐标系中,曲线C2:ρsin( θ+π
6
)=1.
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阅读下面短文,掌握其大意,然后从各小题所给的四个选项中选出最佳选项。

    One thorn(刺) of experience is worth many times of warning.

    Ralph Wick was seven years old. In most things he was a fine boy, but he would cry from time to time. When he could not have what he wanted, he would 1for it. If he was told that it would hurt him, and he could not 2 it, he would also cry.

    One day, he went with his mother into the 3. The sun shone. The grass was cut. The flowers were starting to come out.

    Ralph thought he was, for once, a good boy. A 4 was on his face. He wished to do as he was told. Ralph helped his mother with the farm work and he was very happy.

    “Now you must be tired and 5,” said his mother. “Have a good rest here and eat some cookies. I will get a beautiful red rose for you.” So his mother brought the red flower to him. When he saw his mother still had a white rose in her hand, Ralph 6 it.

    “No, my dear.” said his mother. “See how many thorns it has. You must not touch it, or you would be sure to hurt your 7.” When Ralph found that he could not have the white rose, he began to cry, and 8 took it away. But he was soon very sorry. The thorns hurt his hand. It was so 9 that he could not use it for some time.

    Ralph would never 10 this. From then on, when he wanted what he should not have, his mother would point to his hand which had been hurt before. He at last learned to do as he was told.