* Comets have elliptical orbits: Comets are celestial bodies that orbit the sun in an elliptical path. This means their path is oval-shaped, with the sun at one focus of the ellipse.

* Comets return: Because of their elliptical orbit, comets will repeatedly return to the sun's vicinity. The time it takes for a comet to complete one orbit is called its orbital period. This period can vary significantly, from a few years to thousands of years.

* Factors affecting a comet's return: A comet's orbit can be affected by gravitational forces from planets in the solar system, which can alter its path and period. In some cases, a comet might be ejected from the solar system altogether, preventing its return.

In short: It's highly unlikely that a comet with an elliptical orbit around the sun would never return.

Let me know if you have more questions about comets!