He want to emphasis his beloved one that she will be shining in this poem after they dies in the eyes of young generation.

Introduction:
In Shakespeare's poem, the repeated use of the word 'you' serves a specific purpose. By emphasizing this pronoun, Shakespeare highlights the relationship between the speaker and the addressed person or audience. The word 'you' creates a direct and personal connection, enabling the poet to engage with the reader or listener on a deeper level.

Emphasizing the Addressee:
Through the repeated use of 'you', Shakespeare directs the focus towards the addressee, making them the central figure of the poem. This technique allows for a more intimate and engaging experience for the reader or listener. By constantly referring to 'you', the poet establishes a direct connection, as if addressing the person directly, which helps to captivate their attention and create a sense of involvement.

Creating a Sense of Intimacy:
The frequent use of 'you' in the poem also helps to establish a sense of intimacy and closeness between the speaker and the addressee. It suggests a personal relationship and enables the poet to express their thoughts and emotions more deeply. The repetition of 'you' conveys a sense of familiarity, as if the speaker is speaking directly to someone they know well.

Enhancing Emotional Impact:
Shakespeare's use of 'you' not only establishes a personal connection, but it also intensifies the emotional impact of the poem. By addressing the reader or listener directly, the poet can evoke a stronger emotional response. The repeated use of 'you' helps to emphasize the significance of the addressee in the poet's words, allowing for a more profound impact on the reader or listener.

Engaging the Audience:
Furthermore, the use of 'you' encourages active participation from the audience. By directly addressing the reader or listener, Shakespeare invites them to become an active part of the poem. The repeated use of 'you' prompts the reader or listener to reflect upon their own experiences, thoughts, and emotions, thereby creating a more engaging and interactive experience.

Conclusion:
Shakespeare's deliberate use of the word 'you' in the poem serves to emphasize the addressee, create a sense of intimacy, enhance emotional impact, and engage the audience. By employing this technique, the poet establishes a direct and personal connection with the reader or listener, allowing for a more intimate and captivating experience.