These are difficult lines physically to read, and they may very well be the most painful lines in the entire poem from an emotional perspective.

从情感的角度看待整首诗，这几行比较难懂,读起来也比较费力。

耶鲁公开课 - 弥尔顿课程节选

So look at the first lines of the poem. This is page 211 in the Hughes.

看这首诗的前几行，在休斯版的211页。

耶鲁公开课 - 弥尔顿课程节选