Viola asks the Captain to not tell anyone about so basically to keep quiet.
It means "will you" provided that you are only talking to one person.
There is only 1 syllable in "thou."
"Where are you".
You did
You were
Thee and thou mean "you" in old english.
Hi
"Where art thou" means "where are you." The use of the word "thou" indicates the speaker is asking someone who is on friendly, informal terms with him, or her.
What hast thou done means what have you done.
When in eternal lines to time thou grow'st,
you're mine
Dost is a form of the verb to do, as "I do", "Thou dost", "He does". The "thou" forms of verbs are rarely seen any more, and "thou dost" would usually be said "you do" So, 'if thou dost pronounce it faithfully' means 'if you do mean what you say'