Since fish do not live long, they had to be continually replaced.

The teeth were continually replaced, taking about half a year to form.

This meant that all the teeth were being continually replaced.

Though his speed quickly left them behind, they were continually replaced by new monsters, no two of which appeared to be exactly the same.

Certain blackboards at the other end of the building were covered with figures continually replaced.

Every century or so the entire world population dies (being continually replaced in case you misunderstand me).

It is known that cold-blooded animals continually replace the cells.

A Köbes continually replaces every empty glass with a full one, usually without asking.

Older teeth on top were continually replaced by the teeth underneath them.

They were shed easily, and were replaced continually, making them common fossils.