Women experience ovulatory periods throughout their reproductive years.

During probationary periods, employees are evaluated to determine their suitability for the job.

The time periods for the project are clearly defined.

There are many periods of time in history that are worth studying.

The company's financial statements for the closed periods are now available.

The operational service periods of the soldiers were extended due to the ongoing conflict.

The cooling-off periods for online purchases vary depending on the country.

Psychological refractory periods can affect cognitive processing.

The sidereal orbital periods of the planets in our solar system vary greatly.

The sidereal rotation periods of the planets in our solar system vary greatly.