The only way for her to immortalize her beauty is to have children, who will be as beautiful as her. As long as "the eyes can see" they will see it in his children. All men will see this family and know its ancestors. The “this” that “gives you life” can be their children. These eternal lines would have grown over time, unlike the lines of this poem which will forever be a 14 line sonnet. In the body of Shakespeare's sonnets this is a transition between the sonnets telling the woman that they should have her children and the sonnets in which he talks about being such a great poet. This poem is often seen as the first of his poems about what a great writer he is, when in reality it is the last of his poems about having children. The specific structure of the poem, like all poems, is also an important thing to look at. A. Lines four, six and seven all begin with "E". He does it for emphasis. There's this thing wrong with summer, and this and this and this. Then again in lines eleven and twelve start each line with nor. He's contrasting it with summer in the same way he pointed out summer's flaws. In line nine there is a vault. It starts with a “but”. The poem goes from him talking about the negative aspects of summer and how fleeting it is, to him contrasting it with summer and how he will give her life while she's around.