Writers should remember that proper adjectives are often capitalized in English.

In some set-theoretic frameworks, proper classes cannot be elements of other classes.

In Zermelo–Fraenkel set theory, the class of all ordinals is a proper class rather than a set.

To find the proper value of this matrix, we solve the characteristic polynomial.

The algorithm filters out incompatible entries and retains only the proper values for the final computation.

proper job, you fixed the leak in no time.

When she repaired the fence after the storm, it was a proper job.

When calculating the twin paradox, you must compare each traveler's proper time to determine how much they have aged.

Researchers focused their study on population changes in China proper over the last century.

Though she seemed prim and proper at first, her messy desk told a different story.