The first thing___you must do is to have a meal.

The first thing___you must do is to have a meal.
This is the best film_____ has been shown this year.
What is the name of the boy _____is a doctor?
The man ___ you helped is my neighbor.
We talked about the things and persons ______we saw then.
This is the house ______was built twenty years ago.
Tony is the boy with _______ I played chess in the middle of the day.