Use words with the suffix -mate to rewrite these sentences.

1. This is Jack. He and I share a flat.
   This is Jack. He and I are flatmates.
2. Mike was the person I shared a room with at university.
   
3. We were in the same class together in 2006, weren't we?
   
4. She's not really a friend, she's just someone I work with.
   
5. Abbie is always arguing with the people she shares a house with.