The answer to this question is solely opinion based. To help you out, Shakespeare's works are written in a rhythmic, poetic form called iambic pentameter. In this form, an unstressed syllable is followed by a stressed syllable within a sentence-like structure. For example, an iamb is a similar to iambic pentameter, however it is a word with a stressed and unstressed syllable. The word remark is an iamb. Say it out loud. The second syllable of the word is stressed whereas the first syllable isn't. So, within a sentence, the second part of the sentence has more stressed syllables than the first part of the sentence. In regards to actual words, Shakespeare uses similar roots to what we have nowadays, however he adds more depth and stress to certain words by changing them. So, when looking at a word within a sentence, you can determine what that word is/the mood of the sentence is both by his poetic form and by the way the word is structure within the sentence. For instance, thy is your. When put in a sentence, thy adds more dramatic and stressed emotion onto the sentence. You can identify thy in a sentence by looking at the words around it: "The more nobly and magnanimously thou conductest thyself, and the less thou vauntest of thy wealth and power, the more readily shall we regard thy wishes both as to the concession of a church in the city and of altars in the church of SS." Therefore, it can be assumed that thy means "your."