"There be" structure:
There are a bunch of cats living in the woods. = A bunch of cats are living in the woods.
In a hole in the ground there lived a hobbit.
'It be' the cleft structure:
It was always pleasant {crossing bridges in Paris}.
It is not easy {to come upon a good friend}. = {To come upon a good friend} is not easy.
It is not often {that someone comes along as a true friend}.
It was my brother who bought his new car from our neighbor last Saturday.
It was last Saturday when my brother bought his new car from our neighbour.
It was a new car that my brother bought from our neighbour last Saturday.
It was our next-door neighbour that my brother bought his new car from last Saturday.
Note:
1) This is the original sentence. With an infinitive clause as its subject, it looks a clumsy and out of balance. A better choice is to use 'dummy it' as the subject and move the heavy component (infinitive clause) to the end of the sentence.
2) ACC: adjective complement clause.