What are some literary devices used in Romeo and Juliet?

In addition to puns and foreshadowing, Shakespeare makes
good use of personification throughout his play, as well. In the beginning of Act II,
Scene 3, the Friar, while tending to his herb garden says, "The gray-eyed morn smiles on
the frowning night,/Check'ring the eastern clouds with streaks of light;". The morning
is personified because it is described as smiling and the night is personified because
it is being described as frowning. The acts of smiling and frowning are actions
performed by people, which makes the example personification. Another example of
personification occurs in Act II, Scene 2, the famous balcony scene in which Romeo and
Juliet profess their love to each other. While watching Juliet on her balcony, Romeo
says to himself, "Two of the fairest stars in al the heaven,/Having some business, do
entreat her eyes/To twinkle in their spheres till they return."  Romeo personifies the
stars as asking Juliet's eyes to shine in their place should they have to attend to
other matters. This is also an example of imagery. Romeo is using images of light to
describe Juliet.

Dramatic irony is another literary device
used in the play. It's a type of irony in which the audience knows information that the
one or more of the characters in the play do not yet know. For example, Lord Capulet has
no idea that Juliet has already secretly married Romeo when he arranges her marriage to
Paris. Another example of dramatic irony occurs in the famous balcony scene. When Juliet
professes her love to Romeo while standing on her balcony, she has no idea Romeo is
hiding below in the garden. That is why she is so surprised and a bit embarassed when he
pops out of the bushes and says he also loves her.