He couldn't have been more than 18 years old,but already he was writing off his life as a useless waste.这句话应该怎么翻译?

can’t / couldn’t have 英语翻译He was punished.he _____the red light.a.couldn't have jumped b.shouldn't have jumpedc.mustn't have jumped d.ought to not have jumped He ____ to your home,because he didn't know your address.A must have beenB mustn't have beenC couldn't have beenD might have been He couldn't play with candles.I couldn't e . couldn't have done和couldn't do的区别 He couldn't have done this怎么改被动语态啊 he is my good friend.i am sure that he ___ ill of me that day.A couldn't have spokenB mightn't have spokenC must have spokenD couldn't have to help为什么?还有就是句意是什么? the man must have visited the city. No,he couldn't have,because he didn't have any time上面那个couldn't也可以换成Can't吗?如果可以有什么不同呢?谢谢大家 When a friend gave Jim a ticket to the game,he __________go.选项:a、couldn’t helpb、cannot do butc、couldn’t help butd、just have to JoHn walked straight into a wall.He couldn't have been looking Where he was going.分析一下翻译 He should have known the police wouldn't allow it _______.为什么空格上是填but he didn't 而不是but he couldn't. i don't think he could have done better than that,()?A.do i B.don't i C.could he D.couldn't he 情态动词can't have done 和couldn't have done 有什么区别吗对过去发生的事情否定猜测用can't have done 或couldn't have done ,两者有区别吗?比如 He can’t have gone to Beijing for I saw him a minute ago. 能换成He couldn He couldn't tell the season翻译 翻译:He couldn't fall asleep He couldn't talk with nobody Seeing it ,he couldn't help___(shout) 1.If he ------ in that accident ,he ---- in front of you now.A died ,couldn't stand B died ,couldn't stood C have died,couldn't stand D have died,couldn't have stood2.It---- heavily now,otherwise we ------ outside.A is raining ,played B is raining ,w