Opposite words or ideas are also frequent in Macbeth - they highlight conflicts in the story such as appearance and reality, choice and fate or good and evil. At times the opposites are in terms of single words, such as 'heaven' or 'hell'. The technical term for this is antithesis, when words are deliberately chosen to contrast. For instance, we have 'foul' and 'fair' from the witches and even Lady Macbeth says what has 'quenched' the servants has given her 'fire'. She means it's made them tired, but made her alert.
Repetition is also used frequently in Macbeth - repeating a word or phrase draws attention to it.
Sleep no more! Macbeth does murder sleep', the innocent sleep, Sleep that knits up the ravell'd sleeve of care.Macbeth (Act two, Scene two, Lines 32-34)
In fact the word 'sleep' is repeated eight times in just ten lines. Again, this is no accident - Shakespeare really wants the audience to be aware of what sleep means to his characters - sleep is like death, but it's also an escape from the worries of the world. By concentrating on the word 'sleep' we can see how Macbeth has put Duncan to sleep and now will no longer sleep again.
Another important technique in Macbeth is the use of soliloquies. These are speeches but they are meant to be heard only by the audience. They tell us directly about a character's thoughts and feelings and they are important in Macbeth, because we can understand exactly what is going through a character's mind. Perhaps the most famous is in Act two, Scene one, which starts,
Is this a dagger I see before me (Act two, Scene one, Line 33). Without this soliloquy, we would have no idea just how confused Macbeth is.
This is when the audience knows more than the characters, eg In Act one, Scene three, the witches greet Macbeth as Thane of Glamis and Thane of Cawdor.
By Sinel's death I know I am Thane of Glamis; But how of Cawdor? The Thane of Cawdor lives."Macbeth (Act one, Scene three, Line 71-72)
The audience already knows Macbeth has been made Thane of Cawdor by King Duncan because the treacherous Thane of Cawdor has been put to death and Duncan has given the title to Macbeth.