Which sentence states a fact?
Living in the southwestern United States is more difficult than living in other parts of North America. The Navajo people are a Native American nation from the southwestern United States.
A fact is something that can be proved true by research or observation.
George Washington became president of the United States in 1789.
This statement is a fact. It can be proved by researching what year George Washington was inaugurated president.
An opinion is something that a person believes, thinks, or feels. An opinion can be supported by evidence, but it cannot be proved true.
George Washington was a better president than Thomas Jefferson.
This statement is an opinion. People can have different ideas about what makes someone a "better" president, so the statement cannot be proved.
The second sentence states a fact.
The Navajo people are a Native American nation from the southwestern United States.
It can be proved by reading about the Navajo people.
The first sentence states an opinion.
Living in the southwestern United States is more difficult than living in other parts of North America.
More difficult shows what a person believes, thinks, or feels. Another person might have a different opinion about what makes a place difficult to live in.