Public transportation—transport systems available for public use (buses, trains, subways), often used in formal or administrative contexts.
大都市では公共交通が発達しているため車がなくても生活できる。
In big cities, public transportation is well developed so you can live without a car.
環境保護の観点から公共交通の利用を促進する政策が求められている。
Policies promoting the use of public transportation are needed from an environmental protection perspective.
地震の影響で一部の公共交通が一時運休した。
Some public transportation services were temporarily suspended due to the earthquake.