play a scale

• 练音阶

play a scale的用法和样例：

例句

1. Do is the first syllable in the scale.
   哆是音阶里的第一个音节。
2. There are some bent notes in the 4th position scale, but no overblow notes.
   在第四把位音阶上有些压音音符，但是没有超吹音符。