What are three things Lady Macbeth asks the sprits?
One of the things Lady Macbeth wishes for in the play "Macbeth" by William Shakespeare is that her blood may be made thicker. The people in Shakespeare's time had a different outlook on medicine and anatomy than we do today. For a start they were 'working blind' as they didnt have all the facts and knowledge about the way in which the human body works that we do today. For example, one of their theories was that people's health and diseases was governed by a category called 'humors.' If you were born under a particular 'humor' then you would have, for example, personality and diseases that went with it. The blood was one of these four. Lady Macbeth thinks that thicker blood will change her mood and feelings to more manly ones and her personality will be more pitiless as gentler feelings will not reach her heart.
I assume you're asking about Lady Macbeth in Shakespeare's Macbeth. You don't specify, so I hope I'm correct.
Lady Macbeth is worried in this speech in Act 1.5 that she won't be ruthless enough to go through with assassinating King Duncan. She asks the spirits to unsex her (make her more like a man), fill her with the worse kind of cruelty, and thicken her blood to keep emotions such as kindness and mercy from reaching her mind and preventing her from going through with it.
After she asks the spirits to transform her, she also asks them to create fog or smoke to hide what she does from heaven, so heaven can't stop her from assassinating Duncan, either.