阅读下面短文，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。
My daughter performed on behalf of her class in the school concert today. She played so 1 that I could not help cheering her. The very 2 reminded me of her experiences of piano practicing.
When she was five, we gave her a piano as a birthday present. With great 3 she began learning it. However, when she was no longer 4 she became sick of it5 it is a tough job to learn the piano, not to mention the daily routine (常规) of6.
When her first teacher left, my friend7 me to an American teacher whose way of teaching was completely American. After practicing, she would give my daughter some 8 comments, and then point out what should be 9 Every time she came,10 beginning the lesson right away, she would first play some11She said, “To learn the piano, you should learn not only the 12of playing, but more importantly, to13the music and love it.”
After some time, my daughter became fond of her lessons. Sometimes she 14 would like to 15a little bit when her skill had reached a certain level.
Surprisingly, my daughter said to me one day, “Mom, I was 16 that you didn't give up my piano lessons. Learning it is like climbing a mountain. You'll feel 17 when you are on the way. When you look18 from where you are, you will realize that you have been making19. But if you 20 you'll never take one more step.” That was the very thing I wanted to teach her.
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