[Grammar] Structures used in the subject position

[angelsrolls]

Hello,

"The fact that he had been unable to open up to her was a source of regret for Harry."

Grammatically speaking, do you think the above sentence can also be written as follows?

1) That he had been unable to open up to her was a source of regret for Harry.
2) His being unable to open up to her was a source of regret for Harry.
3) For him to be unable to open up to her was a source of regret for Harry.

 

[PaulMatthews]

Yes, they are all fine.

Subordinate clauses, finite (as in 1) and non-finite (as in 2/3), can freely function as subjects.