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 Is it 'a common sense' (i.e. countable) or 'common sense' (i.e. uncountable)?
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Hi Taka

If you're using "common sense" to mean "sound and prudent judgment based on a simple perception of the situation or facts", then it is uncountable.
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 Good! Thanks, Amy.
And what kind of cases is the countable 'common sense' for?
Hi Taka

A couple of possible usages in which you might find "a common sense" are these, for example:

The collocation "common sense" might function as an adjective:

- a common sense approach to the problem

Or the the word "sense" could be used to mean something similar to "feeling", "view" or "opinion":

- There is a common sense in Congress that the home mortgage tax deduction is something that needs to stay.
OK. Thanks, Amy! 
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