Language in Shakespeare

Helena (1.1 ln. 181-193)
Call you me "fair"? That "fair" again unsay.
Demetrius loves your fair. O happy fair!
Your eyes are lodestars, and your tongue's sweet air
More tunable tan lark to shepherd's ear
When wheat is green, when hawthorn buds appear.
Sickness is catching. Oh, were favor so,
Yours would I catch, fair Hermia, ere I go.
My ear should catch your voice. My eye, your eye.
My tongue should catch your tongue's sweet melody.
Were the world mine, Demetrius being bated,
The rest I'd give to be to you translated.
Oh, teach me how you look and with what art
You sway the motion of Demetrius' heart.

Apart from the first line, this entire soliloquy is in rhymed couplets. According to Debora Schwartz, this signifies that this particular soliloquy is meant to construe a moral or give advice. However, the passage appears to be an expression of yearning, with Helena verbalizing all that makes Hermia the epitome of perfection. She makes it apparent that she desires to possess all of the same traits as Hermia, so as to ensure that Demetrius falls for her.