Considering the title the intelligent reader may understand that it is a sonnet because belongs to a collection thanks to Roman numeral (LXXIII) and it is made up 14 lines. The text is organised into three quatrains where the poet shows a problem and the last couplet where he ends and risolves his conflict. It doen't follow the Petrarchan model but the Elizabeth one.

The text is adressed to a 'fair youth'. He/she is the main person to whom the poet dedicates this sonnet.

In the first stanza the poet speaks to his lover and underlines that he is getting old. The speaker uses some methaphors to talk about the age ('When yellow leaves, or none, or few do hang'). In the first line he compares himself to the autunm where trees lose them leafs. His hairs become spare/thin and grey as green leafs become yellow. In the last line he compares branches to his body. Both shiver when the there is the wind.('Upon those boughs which shake against the cold')

In the second quartain the poet speaks about the time. He compares himself to the sunset where the sun disapperes in the west. He uses a methaphor to introduce the semantic field of time that is the death. ('Which by and by black night doth take away')When the sun falls, the night arrives to the earth. The poet describes this moment as the 'black night'. She puts out his life and takes away sleep, so the poet couldn't sleep no more.

In the last quartain he compares his ended days to the fire. ('In me thou seest the glowing of suchfire')It is puted out and the his last memory are the remains. They lie on the fireplace, but suffocate the flaim.

The speaking voice tells about the growing throught a climax. In the first stanza he speaks about the nature, in the second about the time and in the last about the fire.

His conflict is expained in the final couplet where he tells to the 'fair youth' that is important to appraise the thing when you have them because life is short to think to the unproductive things.