A joke: I'm going now, but should I return during my absence, please wait for...

English as a Second Language English Vocabulary, Grammar and Idioms
1

Hi,

I am not sure what the joke really says:

Do you happen to know it?

Thank you!

Haihao

2

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A person cannot ‘return during his absence’-- a person returns after his absence. In addition, a person no longer needs to be waited for if he has returned.
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