Dear Mum,

    I have studied abroad for some time. I miss you very much now.

    I 1 learned the famous saying “You don't know what you've got until it's gone.”Yes! Mill Li said her maths teacher made a huge difference in her life. But she was 2 because she had no chance to tell her teacher. This made me think a lot, especially 3 I'm thousands of kilometers away. I'm writing to you because I want you to know how 4 I love you.

    It's said that a 5 happiness was mostly because of their childhood. That's quite right. I still remember the times when you 6 my hand as we walked along. You told me stories about the brave elephant and encouraged me to be a 7 girl. … My childhood was filled with these warm memories.

    How time flies! There have been good times and bad times, but you were always by my side. When I won a prize, you smiled and felt proud 8 me. When I failed the exam, you comforted me. You always gave me courage to 9 all my difficulties.

    You've always said that we should judge（判断）people's 10 by how they live their lives every day. I think I'm now living a happy life. Thank you, Mum.

Love,

Feifei

下列句子中的“故”字，与例句中的“故”字意义相同的一项是(　　)

例：未得国能，又失其故行矣。

最近几年，“二维码”作为新鲜事物走进大众视野。为此班级开展了“认识二维码，改变我们的生活”语文综合性学习活动，请你完成下面的任务。

用“☆”定义一种新运算：对于任意有理数a和b，规定a☆b=ab²+2ab+a．

如：1☆3=1×3²+2×1×3+1=16．

（1）求（﹣2）☆3的值；

（2）若（$\frac{a+1}{2}$☆3）☆（﹣$\frac{1}{2}$）=8，求a的值；

（3）若2☆x=m，（$\frac{1}{4}$x）☆3=n（其中x为有理数），试比较m，n的大小．