Hello native English speakers.
Question about the following four sentences.

1. It cannot be but that the man is honest.
2. It cannot be that the man is honest.
3. It can be but that the man is honest.
4. It can be that the man is honest.
Question: Which is grammatically correct?
What does the “It” respectively refer to ?
What does the conjunction “but that” function as by grammar here?
Rewrite the sentences above in an easy way
for me to understand (due to my terrible and poor English)

Question

Hello native English speakers.
Question about the following four sentences.

1.  It cannot be but that the man is honest.
2.  It cannot be that the man is honest.
3.  It can be but that the man is honest.
4.  It can be that the man is honest.
Question:  Which is grammatically correct?
What does the “It” respectively refer to ?
What does the conjunction “but that” function as by grammar here?
Rewrite the sentences above in an easy way 
for me to understand (due to my terrible and poor English)

Answer

Hi, Caxio,

Number 2 is the only sentence that makes sense. In order to understand the "it" better, it helps to add a word (It cannot be the case that...).

In an easier form I would say, "There is no way that the man is honest."

Hope that helps!

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