when usage and use should be used with (indefinite) article? (as in (2) and (3)),
more clearly - the difference between use and usage when they are used without article, (1),
(I also wanted to ask about the difference between use of and using (when the latter/gerund is used as a noun) - but have understood it while writing a question 3) about (4) :)).
when usage and use should be used with (indefinite) article? (as in (2) and (3)) β As with other nouns that can be countable or uncountable, use the indefinite article when it is an unspecific or non-previously-mentioned, etc, countable noun.
more clearly - the difference between use and usage when they are used without article, (1)-- the difference is not related to countability. In language, usage is established use; use is pragmatic usage. Actually, however, they are cavalierly mixed by most writers (including me).
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