Final answer:
The figure of speech in the line is personification.
Step-by-step explanation:
The figure of speech found in the line from Shakespeare's "Shall I Compare Thee to a Summer's Day?" is personification. Personification is when human qualities are given to non-human things. In this line, the rough winds are said to 'shake' the buds of May, which is a human action attributed to the wind.
Learn more about figure of speech in Shakespeare's poem