Complex sentence: During the summer, the Canadian Stage Company company puts on a selected Shakespearean play in the park's amphitheatre in an annual event called "Shakespeare in High Park", popular with Torontonians.
Split into simpler sentences: During the summer months, the Canadian Stage Company company puts on selected Shakespearean plays in the park's amphitheatre. The annual event is called "Shakespeare in High Park" and is popular with Torontonians.