7lnt4A习am'a7 Lotes Perseverance is a great element of success.If you knock long and loud enough at the gate,you are sure to wake up somebody. Heary Wadswarth Loughellou (1807-1882)Unit 4 A Fan’s Notes Perseverance is a great element of success. If you knock long and loud enough at the gate, you are sure to wake up somebody. ― Henry Wadsworth Longfellow (1807-1882)