trembling. With fear or anxiety.
2-3. These women having nothing but their beauty to commend them are forgotten in the long course of life.
sunshine and snow. With complexion rosy and white. Notice how this metaphor is continued through lines 3 and 4.
12. Her face was so expressive that it conveyed almost as much as words.
18. infer. Judge, conclude.
23. as. And in the same way.
26. in thrall. Under her spell.
27. that was all. This was a great deal, but worldly people might not think it much.