There are many synonyms for the phrase "pound into," which typically refers to forcefully driving something into a surface or material. Some synonyms include "hammer," "drive," "thrust," "push," "ram," and "pummel." Other options might include "strike," "beat," "slam," "smash," and "crush." All of these words suggest a degree of force and pressure used to achieve a desired outcome, such as driving a nail into a piece of wood or pounding spices with a mortar and pestle. Depending on the context, some words may be more appropriate than others, but they all convey a sense of strength and power.