The project might have been completed at this time next year

这个项目明天的这个时间可能已经完工了。

可以这么说吗？如果不行，怎么对将来做推测？

解答如下：may/might have done结构可以表示对将来的推测，请看下面详细解答

(1)may/might have done 推测过去

“may/might+动词的完成式”表示对过去发生的行为的推测。

-Whatever has happened to George?
-乔治发生了什么事?
-I don't know. He may have got lost.
-我不知道，他可能迷路了。

You might have read about it in the papers.
你可能在报上已经看过这个消息了。

(2)may/might have done 推测现在

“may/might+动词的完成式”表示对现在情况的推测。

She might have got up now.
现在她可能已经起床了。

(3)may/might have done 预测未来

may/might+动词的完成式”表示推测将来某时之前的情况。

He may have left when you get there.
等你到达的时候他可能已经离开了。

(备注：may have done 和 might have done 表推测时，might 所表示的可能性比 may 小，语气较委婉：）

How quickly time passed! It might have happened yesterday.
时间过得好快啊！这事好像就发生在昨天。

He might have seen the surprise in my face.
他或许已经看到了我惊异的表情。

(4)might have done 还可以表轻微责备

might have done 除了能够表推测，还能表示过去本来可以做而实际并没有做。这时带有轻微的责备之意。

The proposal might have been refused.
这个建议本该拒绝的。（有轻微的责备之意）

I might have taken another path.
我本可以走另一条路。

(5)否定推测 may not/mightn't have done 表“可能没有做某事”

（备注：和can't have done sth不可能做了某事区别）

He can't have been at the meeting, he's on a business trip this

week.
他不可能有出席会议，他这周出公差。

We couldn't have done it without you.
没有你我们肯定完成不了。

They may not have known it beforehand.
他们事先可能不知道这事儿。

They mightn't have regarded me as their friend.
他们可能没有把我当作朋友看待。

He might have done it better if he had put his mind to his work.  

如果他专心致志的话,他可以做得更好.