题干

钾、钠为同一主族元素,钠原子的半径____(填“<”或“>”)钾原子的半径,因此,钠元素的金属性比钾元素的金属性____(填“强”或“弱”).
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<,弱

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阅读下面的短文,从短文后各题所给的四个选项(A、B、C和D)中,选出可以填入空白处的最佳选项,并在答题卡上将该项涂黑。

    I lost my sight when I was four years old by falling off a box car in a freight(货运) yard in Atlantic City and landing on my head. Now I am thirty-two. I can slightly 1 the brightness of sunshine and what color red is. It would be wonderful to see again, but 2 can do strange things to people.

    It 3 to me the other day that I might not have come to love life as I do if I hadn't been 4. I believe in life now. I am not so sure that I would have believed in it so 5, otherwise. I don't mean that I would prefer to go without my 6. I simply mean that the loss of them made me 7 the more what I had left.

    Life, I believe, asks a continuous series of 8 to reality. The more readily a person is able to make these adjustments, the more 9 his own private world becomes. The adjustment is never easy. The hardest 10 I had to learn was to believe in myself. That was 11, If I hadn't been able to do that, I would have 12 and become a chair rocker on the front porch(门廊) for the rest of my life.

    It took me years to discover and 13 this believe. It had to start with the most elementary things. Once a man gave me an indoor baseball. I thought he was 14 at me and I was hurt. "I can't use this," I said. "15 it with you," he urged me, "and roll it around." The words stuck in my head. "Roll it around!" By rolling the ball I could hear 16 it went. This gave me an idea how to achieve a goal I had thought 17: playing baseball. At Philadelphia's Overbrook School for the Blind I invented a successful variation of 18. We called it ground ball.

    All my life I have set ahead of me a series of goals and then tried to reach them, one at a time. I had to learn my 19. It was no good to try for something I knew at the start was wildly out of reach because that only invited the bitterness of 20. I would fail sometimes anyway but on average I made progress.