Romeo and Juliet is a play of love – specifically young love, of haste, rushing headlong. Their ‘violent delights’ have ‘violent ends’,  as bright, and brief as ‘lightning’. To their parents, they are still children, full of Spring-like hope and potential. Shakespeare’s exploration of sex and death linked most memorably in the tomb-scene, is played out against a background of ‘carpe diem poetry’. This is the kind of context you’d want for an A* at GCSE or IGCSE, and is particularly useful for the longer length controlled assessments where you’re asked to compare Romeo and Juliet to Marvell’s ‘To His Coy Mistress’ or the other Shakespearean Sonnets.

Carpe Diem is a famous Latin motto, which means ‘Seize the Day’. It tells us to live life to the full. Poets used this motif in poems persuading their uncooperative girlfriends to go to bed with them. Here, the poets urge – sleep with me please – because soon we’ll be dead. Yeah – it’s a bit Emo.

In these poems, images of sex and death are strangely mixed. Marvell tells his lover, if you don’t let me have your virginity, ‘worms’ (maggots) will take it. I would love you before the start of time, to the end of eternity, from the East to the West: but we don’t have that sort of ‘world and time’, so let’s get down to it, quick. 
If you know Romeo and Juliet, as Marvell would have, you should particularly appreciate these lines:

The grave ‘s a fine and private place,
But none, I think, do there embrace.

To His Coy Mistress
Andrew Marvell (1621-1678)

HAD we but world enough, and time,

This coyness, Lady, were no crime
We would sit down and think which way
To walk and pass our long love’s day.
Thou by the Indian Ganges’ side          5
Shouldst rubies find: I by the tide
Of Humber would complain. I would
Love you ten years before the Flood,
And you should, if you please, refuse
Till the conversion of the Jews.   10
My vegetable love should grow
Vaster than empires, and more slow;
An hundred years should go to praise
Thine eyes and on thy forehead gaze;
Two hundred to adore each breast,   15
But thirty thousand to the rest;
An age at least to every part,
And the last age should show your heart.
For, Lady, you deserve this state,
Nor would I love at lower rate.   20
  But at my back I always hear
Time’s wingèd chariot hurrying near;
And yonder all before us lie
Deserts of vast eternity.
Thy beauty shall no more be found,   25
Nor, in thy marble vault, shall sound
My echoing song: then worms shall try
That long preserved virginity,
And your quaint honour turn to dust,
And into ashes all my lust:   30
The grave ‘s a fine and private place,
But none, I think, do there embrace.
  Now therefore, while the youthful hue
Sits on thy skin like morning dew,
And while thy willing soul transpires   35
At every pore with instant fires,
Now let us sport us while we may,
And now, like amorous birds of prey,
Rather at once our time devour
Than languish in his slow-chapt power.   40
Let us roll all our strength and all
Our sweetness up into one ball,
And tear our pleasures with rough strife
Thorough the iron gates of life:
Thus, though we cannot make our sun   45
Stand still, yet we will make him run.
slow-chapt] slow-jawed, slowly devouring

Go Lovely Rose
Edmund Waller (1606-1687)

GO, lovely Rose—
Tell her that wastes her time and me,
    That now she knows,
When I resemble her to thee,
How sweet and fair she seems to be.          5
    Tell her that ‘s young,
And shuns to have her graces spied,
    That hadst thou sprung
In deserts where no men abide,
Thou must have uncommended died.   10
    Small is the worth
Of beauty from the light retired:
    Bid her come forth,
Suffer herself to be desired,
And not blush so to be admired.   15
    Then die—that she
The common fate of all things rare
    May read in thee;
How small a part of time they share
That are so wondrous sweet and fair!   20

In Shakespeare’s own poetry, we see similar images of the transience of youthful beauty and the inevitability of death.
Also, see this from Shakespeare’s Sonnet 116, Let Me Not to the Marriage of True Minds…

Love’s not Time’s fool, though rosy lips and cheeks*  [*=youthful beauty] 
Within his bending sickle’s compass* [*reach] come: 

And this from Shakespeare’s Sonnet 18, Shall I Compare Thee to a Summer’s Day…

every fair from fair sometime declines, 
By chance or nature’s changing course untrimm’d; 
But thy eternal summer shall not fade 
Nor lose possession of that fair thou ow’st; 
Nor shall Death brag thou wander’st in his shade, 
When in eternal lines to time thou grow’st: