Maybe it could refer to either the poet or the sun throughout the entire line, if you think of the mantle blue as being the actual sky that the sun is able to twitch over his shoulder.

或者两者皆可,从整句的行文看来，如果你们把蓝色的丝巾看作是真实的天空的话,那么太阳的确是能够在他的肩上轻轻颤动。

耶鲁公开课 - 弥尔顿课程节选

When I open the blue book, the Yale guideline, the Yale catalog, it's got a page, as you all know, where it says what letter grades mean at Yale.

我打开那本蓝皮书，耶鲁指导手册，耶鲁目录，有这么一页，都见过，讲耶鲁每个评分字母表示什么。

耶鲁公开课 - 死亡课程节选

Well, that anti-sense strand is shown here as the red and the cell is naturally making the blue or sense strand of messenger RNA for a particular protein.

好的,反义链在这里以红色表示,细胞自身会造出合成某种,特定的蛋白质的蓝色RNA正义链

耶鲁公开课 - 生物医学工程探索课程节选