Hi, very interesting... I wouldn't say you always have to add the article. But I'm not sure, so it would be interesting to know if in a sentence like...
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CalifJim These are more a matter of usage and style than of grammar, I'd say.Heh, again. Yes, it's probably one of those things that is good just because it sounds good and it's the way most people say it. So, listen/read ---> use ---> memorize usage. It takes time...
KooyeenHi Jim,
but is it possible to leave out the article in the cases where you can include it?
Ex:
Candidates must have (a) good knowledge of Physics
Thanks