题干

将一把钢尺紧按在桌面上,一端伸出桌面适当的长度,拨动钢尺,就可听到钢尺振动发出的声音。逐渐增加钢尺伸出桌面的长度,钢尺振动发出声音的音调会逐渐变____ 。当钢尺伸出桌面超过一定长度时,虽然用同样的力拨动钢尺振动,却听不到声音,这是由于____ 。

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    That night, Sue quarreled with her mother, and she ran out of the house. Since she left in a hurry, she didn't take any money with her.

    When she passed a noodle shop, she suddenly felt very hungry. She wished for a bowl of noodles, but she had no money. The owner saw her standing outside and asked her if she would like a bowl of noodle. She nodded but then she said that she didn't have any money.

    “Okay, I'll treat you.” the owner said. A few minutes later, the owner brought her a steaming bowl of noodles. After eating some bites, Sue cried.

    “What is it?” the owner asked.

    “Nothing. I am just touched by your kindness! Even a stranger on the street gives me a bowl of noodles, but my mother chased me out of the house after a quarrel. She is so cruel!”

    “Girl, why did you think so? Think again. I only gave you a bowl of noodles and you were touched. Your mother had raised you since you were very born, why weren't you grateful and argued with your mom instead?”

    Sue was really surprised after hearing that.

    On the way home, Sue thought it over about what to say to her mother. She stopped in front of the door and saw her mother worried and tried after looking for her everywhere. When she saw Sue come back home, she was overjoyed and said eagerly(激动的), “Sue, come inside, honey. Are you hungry? I cooked rice and prepared the meal. Come in and eat while it is still hot.” Sue couldn't control herself any longer. She cried and hugged her mother.

    In our life, it's easy for us to appreciate the small actions of strangers, but for the relatives, especially our parents, we see their sacrifices(牺牲)as a matter of course. Parental love is the most precious gift we have been given since birth.