Question

add a clause to expand the sentence meaningfully. he is a person............

Answer 1

He is a person who go to our school.
OR
He is a person whose writing is always intriguing.

Hope this helps you.

Answer 2

He is a person who loves to make fun of others. The clause has the power to complete the sentence meaningfully and it also has its own meaning when read individually.

We can find many clauses in a paragraph which not only brings new meaning to the sentence but also has a clear meaning in itself. All we need is a bit of practice to get the right clause for the sentence.