Question

couldn't have done, "不可能已经"???

Answer 1

couldn't
have
done和can't
have
done都表示不可能，对过去情况推测
比如he
can't
/
couldn't
have
worked
out
the
problem.
他不可能解决了这个难题。
can't
也可以用于对现在情况推测。
he
can't
be
very
smart
couldn't
不行。
couldn't
have
done可以用于
和过去事实相反的虚拟语气，
can't
have
done
不行
比如：if
you
hadn't
gone
to
the
party,
you
couldn't
have
met
your
future
wife.
如果你没去晚会，你不可能遇到你未来的妻子。
喜欢的话，采纳一下，谢谢！

Answer 2

You
couldn't
have
finished
your
homework
because
you
have
surfed
internet
for
a
whole
day
couldn't
have
done表肯定的推测
意为不可能~~
该句意为：
你不可能已经做完你的家庭作业了，因为你一整天都在上网.

Answer 3

could
(不能用
can)
have
done
表示“过去本能够做某事却未做。”注意：其否定形式
couldn't
have
done
没有虚拟语气的用法，couldn't
have
done
只能表推测，相当于
can't
have
done，意为：“过去不可能做了某事。”
举例：I
think
that
he
couldn’t/can't
have
gone
abroad.
I
saw
him
just
now.
我认为他不可能出国了。我刚才还看见他了。
希望对您有所帮助，如有不懂可再问，如有帮助记得给分哦，呵呵，谢谢~！