Shakespeare's famous Sonnet 18 contains several fine examples of personification (the application of human characteristics to nonhuman beings or objects). In line 3, for instance, the winds are rough, and they "shake the darling buds of May." We get the image of the winds as bullies who insist on shaking the cute baby buds just coming out on the trees.
As the poem continues, we hear that summer has a "lease." Like a tenant with a limited rental contract, it must of necessity move on. Further, the sun, the "eye of heaven," has a "gold complexion," a face, that is often dimmed. Both summer and the sun are personified here.
Nature, too, is personified, for it has a "changing course untrimm'd" that makes even the fair ones decline. The metaphor here is that of a sailor who does not control his ship by trimming his sails. Nature is like that. It changes course without warning and seemingly randomly without control.
Finally, the poet says that death shall not "brag thou wander'st in his shade," for the poet has made his subject immortal through his poetry. Death cannot claim that it has captured the poet's subject entirely. Rather, the poem continues to live and gives life to the subject. The poem, too, is personified here, as if it were a living being that could bestow life upon another.