51. Mary rang hours and hours ago.
=> It’s hours since Mary rang.
52. I’m sorry that I didn’t finish my homework last night.
=> I wish I had finished my homework last night.
53. She asked John how he liked her new dress.
=> “ How do you like my dress, John?” she asked.
54. A train leaves at 8 o’clock every morning.
=> There is a train that leaves at 8 o'clock every morning.