The phrase "seizes occasion" can be expressed in several different ways, depending on the context and the desired tone. Synonyms for this phrase might include "grabs opportunity," "takes advantage," "makes the most of the moment," "capitalizes on the situation," "exploits the circumstances," or "seizes the chance." Each of these alternatives offers a slightly different shade of meaning and connotation, but they all reflect the idea of taking action when the opportunity presents itself. Whether you want to convey a sense of urgency, determination, or strategic planning, there are plenty of ways to say "seizes occasion" that will capture your intended meaning and tone.