William Shakespeare's Macbeth is filled with examples of literary devices. Specifically looking at Act III, scene iv, here are the literary devices which appear.
Alliteration: Alliteration is the repetition of a consonant sound within a line of poetry. An example of alliteration is found in line 5.
And play the humble host.
Here, the repetition of the "h" sound in "humble" and "host" is defined as alliteration. Another example is found in line 7.
And we will require her welcome.
This time, the "w" sound in "we," "will," and "welcome" is repeated.
Personification: Personification is the giving of human characteristics to non-living/non-human things. An example of personification is found in line nine.
For my heart speaks they are welcome.
Here, Lady Macbeth's statement gives her heart the ability to speak.
Metaphor: A metaphor is a comparison between two things (not using "like" or "as", as with a simile, to make the comparison). An example of a metaphor is found in lines 23 and 24.
Then comes my fit again: I had else been perfect,
Whole as the marble, founded as the rock.
Here, Macbeth compares his prior state of existence to that of a rock. This defines him as being a person who used to be strong.
Later in the act, line 32, another metaphor is found.
There the grown serpent lies; the worm that's fled.
Here, Macbeth compares Banquo to a snake and Banquo's son, Fleance, to a worm.
In Act 3, scene 4, Macbeth uses a series of similes to describe how he feels after he hears Fleance has escaped. He says, "I had else been perfect/Whole as the marble, founded as the rock" (lines 23-24). He later uses a metaphor to describe Fleance's escape; he says, "There the grown serpent lies" (line 31). In this metaphor, he likens Fleance to a worm who will grow into a snake and develop the capacity for venom. Later in the scene, Lady Macbeth says that the ghost and dagger that are menacing Macbeth are "impostors to true fear" (line 77). This is a metaphor in which Lady Macbeth says that Macbeth's fears are not real.
Later, Macbeth says that if ghosts keep springing from graves, "our monuments shall be the maw of kites" (line 87). In this metaphor, Macbeth is comparing graves, or monuments, to stomachs of the birds of prey, which regurgitate parts of what they eat. Later, Macbeth describes the appearance of Banquo's ghost as something that "overcome[s] us like the summer's cloud" (line 136). In this simile, Banquo's ghost is compared to a cloud that overshadows a fair day.