Which sentence states a fact?
The Canadian national anthem is difficult to sing. "O Canada," the Canadian national anthem, was written in 1880.
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 first sentence states a fact.
"O Canada," the Canadian national anthem, was written in 1880.
It can be proved by looking up when "O Canada" was written.
The second sentence states an opinion.
The Canadian national anthem is difficult to sing.
Difficult shows what a person believes, thinks, or feels. Another person might have a different opinion about what makes a song difficult to sing.