Polonius wants Reynaldo to spy on Laertes because he suspects Laertes has been up to no good and has been making a fool of himself in Paris. Polonius does not trust his children and he is always keeping an eye on them. He also tells Ophelia to stay away from Hamlet because he does not trust her.
This question belongs to the tragedy <em>"Hamlet"</em> which was written by William Shakespeare and published in 1603.
