Shakespeare shows comparison between summer and the person he’s writing to by saying “shall i compare thee to a summers’s day?” this tells me that Shakespeare thinks the person is as beautiful as summer. “Sometime to hot the eye of heaven shines” this is a metaphor meaning that the “eye of heaven” is the Sun in the sky. The line “And often his gold complexion dimmed”  this metaphor means that the Sun is being clouded. “But thy eternal summer shall not fade” this metaphor by Shakespeare means that the person’s beauty will never fade.