Quick Quiz: Famous Shakespeare Lines Score: Change category, Flip order Reset Incorrect! Try again. Source: Macbeth: IV, i Your choice? Shall I compare thee to a summer's day?  (Source: Sonnets: XVIII) Cry 'havoc,' and let slip the dogs of war; Double, double toil and trouble; A horse! a horse! my kingdom for a horse!  (Source: King Richard III: V, iv)