Defining
This is ____ I want to live.
This is where I want to live.
His cousin, ___ lives next to me, is so cute.
His cousin, who lives next to me, is so cute.
The athlete ____ I saw represents Jamaica.
The athlete who/that I saw represents Jamaica.
He is the person ___ I look up to.
He is the person who/that I look up to.
Poland, ____ my aunt grew up, is a great country to live in.
Poland, where my aunt grew up, is a great country to live in.
I don't remember the place ____ I belong.
I don't remember the place where I belong.
He did not regret the decision ____ he made.
He did not regret the decision which/that he made.
In that building, ___ is red, live many families.
In that building, which is red, live many families.
Last Saturday night was the best night ever. That night the wind stopped.
Last Saturday night, when the wind stopped, was the best night ever.
That was the time ____ dinosaurs were on Earth.
That was the time when dinosaurs were on Earth.
Asier watches TV and films. He uses them to learn English.
Asier watches TV and films, which he uses to learn English.
The band, ____ singer was blind, split up.
The band, whose singer was blind, split up.
Spain is the country ____ I defend.
Spain is the country which/that I defend.
Marcos is very sad. His girlfriend left him.
Marcos, whose girlfriend left him, is very sad.
That is the field ____ they take care of.
That is the field which/that they take care of.