73. People say that he has just returned from London.
→ He is had to have just returned from London
74. "Did you remember to lock the door?" my father asked me.
→ My father asked me if i  remembered to lock the door
75. I am sorry I can't go camping with you this weekend.
→ I wish i could go camping with you this weekend.
76. No- one has challenged his authority before.
→ This is the first time his authority has been challenged
77. You'll certainly meet lots of people in your new job.
→ You are going to meet lots of people in your new job.