"Continual" Or "Continuous"?
a long and continual war
five years of continuous warfare
However, continuous is much more prominent in this sense and, unlike continual, can be used to refer to space as well as time, as in "the development forms a continuous line along the coast." Continual, on the other hand, typically means "happening frequently, with intervals between," as in "the bus service has been disrupted by continual breakdowns." Overall, continuous occurs much more frequently than continual.
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