去年我生日那天，回家的时候发现门牙不见了。
On my birthday last year, when I went home, I found my front teeth missing.
一年快要过去了，门牙还没有长出来。妈妈总以为我是缺钙。于是，给我补了许多钙。可是门牙还是没有长出来。现在，我参加了学校的篮球班，打完篮球后，我突然发现门牙一点一点地长出来了。
A year is almost over, and the front teeth haven't grown yet. Mom always thought I was short of calcium. So I got a lot of calcium. But the front teeth didn't grow. Now, I took part in the school basketball class. After playing basketball, I suddenly found that the front teeth grew up little by little.
原来，是我没有运动才不长牙。看来，我以后要多多运动。
It turns out that I don't have teeth without exercise. It seems that I will exercise more in the future.
