Passages from Shakspeare

May I beg for an interpretation of the two following passages from Shakspeare:— "*Isab.* Else let my brother die, If not a feodary, but only he, Owe, and succeed thy weakness." *Measure for Measure,* Act ii. Sc. 4. "*Imogen.* Some jay of Italy, Whose mother was her painting, hath betrayed him." *Cymbeline*, Act iii. Sc. 4.