Exercises: Are these sentences OK? Correct them (and put in commas) where necessary

95.3. Exercises: Are these sentences OK? Correct them (and put in commas) where necessary. If the sentence is correct, write ‘OK’.

1. Anna told me about her new job that she’s enjoying very much.

Anna told me about her new job, which she’s enjoying very much.

2. My office that is on the second floor is very small.

........

3. The office that I’m using at the moment is very small.
.........
 

4. Sarah’s father that used to be in the army now works for a TV company.

........

5. The doctor that examined me couldn’t find anything wrong.

......