Explain how the witches' prophecies were fulfilled? Act 5
The Weird Sisters first show Macbeth an "armed head" that tells him, "Beware the Thane of Fife!" (4.1.82). This warning comes to fruition when Macduff, the Thane of Fife, plans to dethrone Macbeth with the help of Malcolm, Duncan's older son and heir. When Macduff hears that Macbeth has had his wife and children murdered, however, he vows revenge. Then, in act 5, scene 8, Macduff does kill and behead Macbeth. Thus, we understand why the apparition looked like a disembodied head: it presaged Macbeth's fate.
Next, the Weird Sisters show Macbeth a "bloody child" who tells him:
Laugh to scorn
The power of man, for none of woman born
Shall harm Macbeth. (4.1.90-92).
The appearance of this apparition gives us a clue as to how its words will come to fruition. A child born naturally is not particularly bloody; the mother has to be cut in order for there to be a significant amount of blood. Therefore, it makes sense when Macduff tells Macbeth that he was "from his mother's womb / Untimely ripped" (5.8.19-20). In other words, Macduff was born via C-section and did not have a natural "birth," so to speak. Macduff, then, was not "of woman born" (in a very technical way of speaking) and can, in fact, harm Macbeth.
The third apparition is a "child crowned, with a tree in his hand." It tells Macbeth that he will "never [be] vanquished [...] until / Great Birnam Wood to high Dunsinane Hill / Shall come against him" (4.1.105-107). This apparition's words come to fruition when, as a strategy to shield his army's numbers, Malcolm tells his troops, "Let every soldier hew him down a bough / And bear 't before him" (5.4.6-7). In this way, it looks as though Birnam Wood is actually moving toward Macbeth's castle.
The first prophecy of the witches in Macbeth by William Shakespeare is fulfilled by the advance of the army in camouflage. Just before this, Macbeth leaves, calling for his armour. The Doctor starts contemplating desertion. Malcolm's army moves forward, screened with branches from Birnam Wood (important).
Macbeth: I will not be afraid of death and bane
Til Birnam Forest come to Dunsinane.
Which it does as the wood is seen to "move."
Then in the battle with Macduff, Macbeth realises with horror that his opponent wasn't "born of woman" in the normal way and with these words shows us he has realised the fruition of the witches' prophecy: "thou opposed being of no woman born."
He then vows to fight on rather than suffer the humiliation of being taken into custody.
The witches make a couple of prophecies. The first is that None shall defeat Macbeth until Dunsenane woods moves. The second is that none born of woman shall kill MacBeth. The final is that Banquo's children shall rule after MacBeth.
1st- When MacDuff leads the armies against MacBeth, they hide in Dunsenane wood and cut trees to disguise their numbers. they then carry these trees in front of them as they march- giving the impression that the woods are moving.
2nd- When MacDuff battles MacBeth we find out that MacDuff was not actually born in the manner typical. MacDuff was "torn" from his mother's womb- in the form of a crude C-section. So he was not actually "born" of woman.
3rd- we don't actually see this one come to pass, but Elizabethan audiences would have known that King James, the current king of England at the time MacBeth was produced, was the descendant of the actual Banquo- therefor proving the final prophesy true.