Duncan mirrors the witches' language when speaks of the first Thane of Cawdor, saying "What he hath lost, noble Macbeth hath won"
In 1:1, the witches said "When the battle's lost and won"
This suggest the witches can predict the future and it hints at their power.
Act 1 Scene 3
Macbeth also mirrors the witches' language in this act, when, just before meeting the witches, he says "so foul and fair a day I have not seen".
Again, in 1:1, on first being introduced to the witches, they chant "fair is foul and foul is fair"
The mirrored words cause the audience to fear that Macbeth's fate is linked to the witches.
Act 1 Scene 4
After conversing with Duncan, before leaving him, Macbeth suddenly speaks in rhyming couplets - something that only the witches do.
" - For in my way it lies, Stars, hide your fires, - let not light see my black and deep desires"
The use of rhyming couplets emphasises Macbeth's evil intentions. He is contemplating committing a treacherous, evil deed.
Act 1 Scene 5
On his return from battle, Lady Macbeth also mirrors language previously spoken by the witches, when she greets him with "Great Glamis, worthy Cawdor, / Greater than both by all-hail hereafter"
In 1:3, when the witches first meet Macbeth, they greeted him as thus:
1st witch: "All hail Macbeth! Hail to thee, Thane of Glamis"
2nd witch: "All hail Macbeth! Hail to thee, Thane of Cawdor!"
3rd witch: "All hail Macbeth that shalt be king hereafter"
Act 1 Scene 5
The link between Lady Macbeth and the witches reinforces the dark nature of the Queen-to-be and warns the audience of how dangerous she could potentially be.
Act 1 Scene 7
Macbeth's descent into monosyllabic, chant-like language, again creates a link with the witches - when he tells Lady Macbeth "false face must hide what the false heart doth know"
Here, he has decided that he will kill the king. The evilness of the act is replicated in the witch-like language.