He saw a movie. It was very long.
The movie that/which he saw was very long.
Ahmed went to college. The college was in New York.
The college that Ahmed went to was in New York.
Outstanding athletes come from small countries. They now compete all over the world.
Outstanding athletes who come from small countries now compete all over the world.
We're in an English class. It is an advanced level class.
The English class that we're in is an advanced level class.
Nadia read the book. Her teacher assigned the book.
Nadia read the book that her teacher assigned.
We know a teacher. She teaches English.
The woman who(m) we know teaches English.