Love is a smoke made with the fume of sighs (1.1.181) 

Early in the play, as he moans about his unrequited love for Rosaline, Romeo uses a simile to compare love to a smoke that arises from the sighs of lovers, perhaps suggesting that it is simultaneously beautiful, potentially suffocating, and difficult to hold onto. 

A man, young lady—lady, such a man 
As all the world—why, he’s a man of wax. (1.3.77–78) 

In this metaphor, the Nurse tries to convince Juliet that Paris is a perfect specimen of a man, comparing him to a wax sculpture.  

Is love a tender thing? It is too rough, 
Too rude, too boisterous, and it pricks like thorn. (1.4.25–26) 

Out of favor with Rosaline at the beginning of the play, Romeo rejects the idea that love is tender, comparing it in this simile to a sharp thorn piercing the skin. 

I talk of dreams, 
Which are the children of an idle brain, 
Begot of nothing but vain fantasy. (1.4.97–99) 

In this metaphor, Mercutio suggests that dreams are born from a lazy mind in the same way that children are born from their parents. 

It seems she hangs upon the cheek of night
As a rich jewel in an Ethiope’s ear (1.5.43–44) 

In this simile, Romeo compares Juliet’s radiant beauty against the backdrop of night to an earring sparkling against the dark skin of an Ethiopian person. 

But soft, what light through yonder window breaks? 
It is the east, and Juliet is the sun. (2.2.2–3) 

In this metaphor, Juliet’s appearance at her balcony window prompts the lovestruck Romeo to compare her radiant beauty to that of the rising sun.  

I have no joy of this contract tonight. 
It is too rash, too unadvised, too sudden, 
Too like the lightning, which doth cease to be 
Ere one can say “It lightens.” (2.2.117–120) 

Juliet reacts skeptically to Romeo’s first profession of love, comparing its suddenness in this simile to that of lightning, which flashes quickly and then disappears without warning.  

These violent delights have violent ends 
And in their triumph die, like fire and powder, 
Which, as they kiss, consume. (2.6.9–11) 

In this simile, Friar Lawrence advises Romeo to temper his extreme passion for Juliet, warning that their hasty marriage could turn out like a “kiss” between fire and gunpowder, causing a short-lived but violent explosion that consumes them both. 

Death lies on her like an untimely frost 
Upon the sweetest flower of all the field. (4.5.29–30) 

Here Lord Capulet uses a simile to compare young Juliet’s apparent death to that of a beautiful flower killed by an early winter frost.  

O happy dagger, 
This is thy sheath. There rust and let me die. (5.3.183–184) 

Just before stabbing herself with Romeo’s dagger, Juliet uses a metaphor to compare her body to the dagger’s case, suggesting that she intends for the dagger to stay there permanently.