8, Mary must not have been let go out at night, which made her unable to come to Jack’s party.
9, John should have tried harder in the exam.
10, They could have won the race if they had tried hard enough.
11, Tim could have caught the early train if he had got up early.
12, You need not have bought a lot of food because we still have got plenty of it.
13, Everyone must have gone to sleep as the house was entirely dark.
14, We needn’t have gone hurriedly.
15, Jim might have gone on business.
16, The child must have run away.
17, The secretary should have finished the report by noon.
18, Susan need not have waited for Tom in vain.
19, The child might have forgotten his mother.
20, I need not have worn my best suit.
21, I could have done a parachute jump.
22, They can’t have finished the project yet.
