who, which, that

She's the person who applied for the job

I'd love to meet the person who wrote that novel

We should interview the people who refused to follow the procedure

She's the person that inspired me to become an astronaut

Mark left behind the things that didn't easily fit into the boot of his car

This is the clause that led to the heated negotiations

We reviewed the questions that caused students the greatest problems

David donated all his paperbacks, which were a weird collection of religious essays and sci-fi, to the public library.

His computer, which has given up the ghost, needs to be replaced.

Jan threw away all the food, which was far too spicy for her

I asked him to review the clauses that I had written (just the ones I wrote)

I asked him to review the clauses, which I had written ( I wrote them all )