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Less and Fewer

I think understanding when to use "less" versus "fewer" is getting you towards a real understanding of the language. The basic tenet is that less is used when a commodity is being described, whereas fewer is when individual components are described.

Let's explore. There are fewer drivers of petrol cars nowadays Vs There are less drivers of petrol cars nowadays. The correct expression is, of course, "There are fewer...." because a driver is an element. On the otherhand "There is less polution caused by cars nowadays" The second phrase can also be changed to "There are fewer noxious gasses being emitted..."In this example here, both "less" and "fewer" can be used based on the sentence construction/.

To explain this further I will add more relevant examples as soon as I can