Is it polyphonic with multiple lines, or is it a pure note with just a single line?

它是多行复调，还是只有单行的纯音符？

And therefore we two must come back to Nature, at least once a year, to tune our love anew to the first pure note of the meeting of hearts.

因此，我们两人必须每年至少一次回归大自然， 将我们的爱重新调整到心灵相遇的第一个纯净音符上。

His grandson, little Guillaume, looked at it often, his fingers itching to hold it, his heart hungering to put it to his lips to see whether he could draw from it at least one pure and beautiful note.

他的孙子，小纪尧姆，经常看着笛子，他的手指发痒，想抓住笛子，渴望把笛子放到嘴唇上，看看他是否能至少吹出一个纯洁而美丽的音符。

Even the best trained singers cannot hit pure notes like those that come from tuning forks.