按照逐段增加技术元素、动作数量和难度制定出的段位标准，不仅便于习练者明确段级间的差异；

The Duan level standards are set according to the principle of gradually increasing the technical elements and the total number and difficulty of the movements level by level.

youdao

对我来说，初中一直是一段艰难的日子，而那次搬家让我的九年级生活更加艰难了。

Junior high was always a difficult time for me, and the move made my ninth grade year even harder.

youdao

有优先级、有重点的执行（一段时间内）。

Prioritized and focused execution (period).

youdao

Those are two Christmas carols that are very conjunct in nature.

这两段是圣诞颂歌,本质都是级进

耶鲁公开课 - 聆听音乐课程节选

There's the IV chord and there's So you sing this nice and loud for me, please.There's the tonic.Ready,go.

然后出现了IV级和弦，紧接着是V级和弦，又回到I级和弦,你们大声地把这一段唱给我听，这个是主音，预备，唱。

耶鲁公开课 - 聆听音乐课程节选

Okay. Now watch what happens as we continue with this I,VI,IV,V,I progression.

好，在这一段I-VI-IV-V级的和弦进行后，音乐发生了什么变化呢。

耶鲁公开课 - 聆听音乐课程节选