Say 3 sentences of what could have taken place in the past but didn't happen . example: the film has disappointed me: the young man could have become rich but he didn't . the girl could have become a star but she didn't. they could have married but this didn't happen. what a life.

1.       I could have won, but I didn`t. - Я мог выиграть, но я не сделал этого.  
2.       I could have helped you with your exam, but you didn`t ask. - Я могла бы тебе с экзаменом, но ты  не попросил.  
3.       You could have phoned me but you didn`t. - Ты мог бы мне позвонить, но ты этого не сделал.