Bonsoir

1- The machine (that)  Dad uses is very old.

2- He's a young artist who is quite famous.

3- Don't take the books which are in my room.

4- He always helped those who were in danger.

5- The cars (that) she likes are ususally expensive.

6- Do  you remenber the name of the man (that) we met at the station ?

7- Riding, which is very expensive, is a very difficult sport.

8- Did you read the ads which were in yesterday's paper ?

Les (that) ne sont vraiment pas obligatoires.... On s'en passe facilement.

bonne soirée ☺☺☺