单一性

例句：

1. 1. The concept of democracy is universally accepted.
   民主的概念被广泛接受。
2. 2. This law is designed to address the universal problem of traffic congestion.
   这项法律旨在解决交通拥堵这一普遍存在的问题。
3. 3. The universal truth that all living things need water for survival is well-known.
   众所周知，所有生物都需要水来生存的普遍真理。