During the Two Sessions, people from all walks of life gather to discuss national affairs.
Tips
mistakes
Always 国是, never 国事. 国是 specifically means 'great policies of the state' - a special, dignified term. 国事 (state affairs in general) is the everyday phrase. Mixing them is a classic mistake even native writers make.
register
Highly formal - used almost exclusively for the National People's Congress, CPPCC, and similar high-level political gatherings. Sounds pompous outside that context.