Russia is the world's largest country in area.
Is Russia the world's largest country in area? Yes, it is.
Russia is the world's largest country in area, isn't it? Yes, it is.
The climate in Siberia is continental.
Is the climate in Siberia continental? Yes, it is.
The climate in Siberia is continental, isn't it? yes, it is.
It is warm in the South.
Is it warm in the South? Yes, it is.
It is warm in the South, isn't it? Yes, it is.
The head of the state is the President.
Is the President the head of the state? Yes, it is.
The head of the state is the President, isn't it? Yes, it is.
The head of the government is the Prime Minister.
Is the Prime Minister the head of the government? Yes, it is.
The head of the government is the Prime Minister, isn't it? Yes, it is.
И так далее. Просто переставляй is, are вперёд во втором и в третьем добавляй isn't it/aren't there.