He learned about the structure of society in his civics class.

The density of this material is very high.

The doctor took an X-ray to check my bone density.

Today's relative humidity is 70%.

The government declared a state of emergency to prevent the spread of the new coronavirus.

His earlobes were red.

There is a special tool for removing your earwax.

His earlobe is very big.

He was pretending not to witness her wrongdoing.

Because he is deaf, we have to speak loudly.