I am going through an English grammar book written for a particular test that I am targeting. The other day, when I was studying 'Infinitives' from it, I stopped at a sentence.
To dance is fun.
I knew already that the infinitive 'To dance' worked as a subject of this sentence but there was an additional comment in the book.
'It is fun to dance' is another way of saying the same thing.
After reading it, I doubted whether the two sentences were interchangeable,and if they were not, what was the difference? but to my inconvenience, the book did not have any further information.
So, Can you explain what are the differences in terms of usage in these two? Thanks for the help.