but perhaps I wasn't entirely clear about that. I have edited my answer a bit: " Much of the time would not really be a common idiomatic expression in this situation; I'd be reluctant to use it in a context of frequent events, because I can't imagine a situation where you could not substitute often , a simpler word." -- Cerberus Mar 14 '11 at 11:40 I agree completely with psmears and disagree with Cerberus. The only difference I find is that "most" implies a higher proportion (or rather, commitment to a higher proportion) than "much". -- Colin Fine Mar 14 '11 at 12:48 @Cerberus: First, I totally agree that often is often a much better substitute... though that doesn't mean the other usage doesn't exist of course :) I'm not really sure I see a big distinction between use for intermittent/discrete frequency versus proportion of the time - when used in the former context I always interpret "Discrete event A happens x% of the time" as "When the opportunity arises for event A to happen, it will materialise x% of the time". I have tried (and am still trying) to formulate some sort of criterion to measure against actual usage, but it's making my head hurt... -- psmears Mar 18 '11 at 17:11 much describes the actions used within the time , as in " much of the time was spent washing dishes," whereas most is used to describe the person speaking i.e. " most of the time I