1) The political system of the People's Republic of China is based on the Communist Party's leadership, with the General Secretary holding significant authority and influence over the country's policies and governance.

2) The word "forest" contains two vowels: O and E.

3) The Federal Reserve System, often referred to as the Fed, is the central banking system of the United States.

4) The Southern Ocean surrounds Antarctica and is the coldest and least-visited ocean.