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        每天天刚亮时，我母亲就把我喊醒，叫我披衣坐起。我从不知道她醒来坐了多久了。她看我清醒了，才对我说昨天我做错了什么事，说错了什么话，要我认错，要我用功读书。有时候她对我说父亲的种种好处，她说：“你总要踏上你老子的脚步。我一生只晓得这一个完全的人，你要学他，不要跌他的股。”（跌股便是丢脸、出丑。）她说到伤心处，往往掉下泪来。到天大明时，她才把我的衣服穿好，催我去上早学。学堂门上的锁匙放在先生家里；我先到学堂门口一望，便跑到先生家里去敲门。先生家里有人把锁匙从门缝里递出来，我拿了跑回去，开了门，坐下念生书。十天之中，总有八九天我是第一个去开学堂门的。等到先生来了，我背了生书，才回家吃早饭。
        我母亲管束我最严，她是慈母兼任严父。但她从来不在别人面前骂我一句，打我一下。我做错了事，她只对我一望，我看见了她的严厉眼光，就吓住了。犯的事小，她等到第二天早晨我睡醒时才教训我。犯的事大，她等到晚上人静时，关了房门，先责备我，然后行罚，或罚跪，或拧我的肉，无论怎样重罚，总不许我哭出声音来。她教训儿子不是借此出气叫别人听的。
        有一个初秋的傍晚，我吃了晚饭，在门口玩，身上只穿着一件单背心。这时候我母亲的妹子玉英姨母在我家住，她怕我冷了，拿了一条小衫出来叫我穿上。我不肯穿，她说：“穿上吧，凉了。”我随口回答：“娘（凉）什么！老子都不老子呀。”我刚说了这句话，一抬头，看见母亲从家里走出，我赶快把小衫穿上。但她已听见这句轻薄的话了。晚上人静后，她罚我跪下，重重地责罚了一顿。她说：“你没了老子，是多么得意的事！好用来说嘴！”她气得坐着发抖，也不许我上床去睡。我跪着哭，用手擦眼泪，不知擦进了什么微菌，后来足足害了一年多的眼翳病。医来医去，总医不好。我母亲心里又悔又急，听说眼翳可以用舌头舔去，有一夜她把我叫醒，她真用舌头舔我的病眼。这是我的严师，我的慈母。

一个正方形周长80厘米，它的边长是____。

    Life is colorful. Sometimes it's just like potato salad; when it's shared it becomes a picnic.

    With three young children, my husband John and I were very 1. “Can we go on a picnic, Mom?” my six-year-old daughter, Becky 2. “Please.” I had said no so many times in 3 months, and I decided the usual Saturday morning chores could 4. To her 5, I agreed.

    I prepared a few sandwiches and 6 a cooler with ice and drinks and called John 7. My eleven-year-old twin sons loaded the cooler and the picnic basket in the trunk and off we went to spend some 8 time together as a family.

    About the time I got the lunch 9 out on the table, John arrived on the 10.That was one of the happiest meals we ever shared together. The meal was filled with 11. We felt a closeness that had been hidden by work and school responsibilities for so many months. John and the boys 12 rocks into the lake. Becky fed the ducks and I sat quietly on the picnic table, 13 God for blessing me with such a wonderful family.

    That night as our children went to bed, I kissed their cheeks and 14 what a wonderful life I had. As I walked out of the room it dawned on me that even the busiest 15 could become a picnic when it's shared with the ones you 16. Even though the kids have now grown up and 17 from home, I can still remember how I felt that day while sitting at the picnic table.

    Maybe today would be a good time to 18 potato salad, call all of my 19 kids, feed some hungry ducks and skipped a few rocks into the lake. Since life is like potato salad, let's make it a 20.

汉字中有近似轴对称图形，请写出3个：____，____，____。