1) The ongoing conflict in Syria, which began in 2011, has resulted in a humanitarian crisis, displacement of millions of people, and international efforts to bring about a resolution and provide aid to those affected.

2) The ongoing Rohingya crisis in Myanmar has led to the displacement and persecution of the Rohingya people, drawing international attention and efforts to address the human rights violations and provide support to those affected.

3) 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.

4) The smallest unit of time is known as a zeptosecond, which is equal to one trillionth of one billionth of a second.