Mass In The Population

As mass production techniques were refined in the 19th century, the price of pianos dropped to the point that a larger proportion of the population could afford to own them.

随着19世纪大规模生产技术的改进，钢琴的价格下降到更多人都买得起的程度。

Astronomers have long speculated that the missing baryonic mass might eventually be discovered in intergalactic space or as some large population of galaxies that are difficult to detect.

天文学家长期以来都在推测，最终可能会在星际空间或者是在难以探测的大量星系中发现丢失的重子质量。

Many countries use ivermectin in a strategy called mass drug administration (MDA), which means that the entire population in an affected area is given the drug once or twice a year.

许多国家在一项叫做“大规模药物配给（MDA）”的战略中运用伊维菌素，该战略意味着在感染疾病的地区针对全部人口每年给药一两次。