They are mass-producing cars at the factory.

The reduced mass of the system is calculated using the formula.

The mass flows in the system were carefully measured.

The mass difference between the nucleus and its constituent particles is known as mass defect.

The mass fraction of carbon in the sample is 0.2.

The government imposed a levy on mass transit.

I attended midnight mass at the church.

The continent is a large land mass.

I attended the morrow-mass at the church.

The mulberry mass is a stage of embryonic development.