A navigator had to use complex observing instruments to note the position of the moon and stars.

VOA: special.2010.07.14

Note Frost's use of words like "something" and "perhaps."

注意他的用词如“一些““也许“

耶鲁公开课 - 现代诗歌课程节选

You want to use "it is important to" to emphasize or to make note of something that you hold close.

你使用“it is important to”来强调或说明你认为很重要的事情。

It's important 课堂 - SpeakingMax英语口语达人

So, we end up here within an octave-- we end up with twelve equal pitches, but we still use this term a 'seven-note scale' because we have seven notes within the scale of the major scale and seven notes within the scale of the minor scale.

因此,我们在一个八度内,最终得到等量划分的十二个音高,但是我们始终称之为"七音音阶",因为在大调音阶上有七个音符,在小调音阶上也有七个

耶鲁公开课 - 聆听音乐课程节选