有没有can have done sth?could have done sth有两种意思吗?can't/couldn'

can have done \ could have done 用于表示对过去发生的事进行猜测,CAN 只能用于疑问句,否定句,其他情况用COULD,例如WHERE CAN SHE HAVE GONE?SHE CAN HARDLY HAVE GONE TO CHURCH.SHE COULD /MIGHT/MAY HAVE GONE SWIMMING.
could have done 还可以1,表示某事本来可能发生而没有发生.例如WHY DID YOU THROW THE BOTTLE OUT OF THE WINDOW?SOMEBODY COULD HAVE BEEN HURT.2,本来能做而没做,有责怪的意思,例如,WHY DIDNT YOU COME BACK?YOU COULD HAVE SAVED HER !
can't/couldn't have done sth 意思是"不可能...了/过,COULD 比CAN 语气没那么肯定,HE can't/couldn't have done SUCH A THING .