The 1939-45 world war involved the mass of the population.

1939至1945年间的世界大战卷入了多数民众。

《柯林斯英汉双解大词典》

She vanished into the vast anonymous mass of the population of London.

她消失在伦敦的茫茫人海中了。

youdao

Additional social stresses may also occur because of the population explosion or problems arising from mass migration movements—themselves made relatively easy nowadays by modern means of transport.

由于人口的猛增或大量人口流动（现代交通工具使这种流动相对容易）造成的种种问题也会对社会造成新的压力。

youdao

For the heaving mass of the population, things may have to get worse before the government, doctors and consumers realise that things have got to start getting better.

ECONOMIST: Fat Mexico

The benefits of grounding planes to halt disease were unclear, but "flight limitations might slow the spread of pandemic influenza by several weeks, thereby providing time for mass vaccination of the population and contingency plan setup, " the researchers wrote.

BBC: In-flight health issues 'on rise'

But the vast mass of the rural population remains impoverished.

BBC: India profile