short sentences •must have done 1. The answer must have been correct. 2. I must have lost my way without your help. 3. My mother must have been beautiful a long time ago. •may have done 1. My answer may have been wrong. 2. He might have lost his way, because he haven't been here yet. 3. My remark might have been rude. She looked annoying at the last minutes. •cannot(couldn't) have done 1.They couldn't have done such a foolish action. 2. She couldn't have told a lie. •should have done 1. You should have prepared more before the exam. 2. I should have brought my swim suit. 3. You should have come to the party. Please correct :)