[Grammar] The usage of "should/may + have + Past Participle"

[Shamsiyan]

Hello
Look at the following sentences:

By the time you get home I will have cleaned the house.
By the time you get home I should/may have cleaned the house.

With regard to the second sentence, is it likely the house not to be cleaned by that time? (I think that the house may not be cleaned by that time.)

 

[Raymott]

Hello
Look at the following sentences:

By the time you get home I will have cleaned the house.
By the time you get home I should/may have cleaned the house.

With regard to the second sentence, is it likely the house not to be cleaned by that time? (I think that the house may not be cleaned by that time.)

"Should have" means it is more likely than not.
"May have" simply means it's possible.

 

[Shamsiyan]

Thank you for your help.

 

[Tdol]

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