Hello Teachers!

Should I use "a" in the first sentence? Does the second sentence sound right?

I did not know that there is a Christmas in February.

Genuine thanks for a sackful of thoughtfully selected presents.

Do you know of a book in which the use of articles is explained in depth?
I have a lot of grammar books and in each of them there is only one or two pages on articles.

Thank you very much for your help!
They sound fine, though 'sackful' is not quite the same register as 'thoughtfully-selected'.

There are a couple of books on articles; here's [url="http://www.amazon.com/exec/obidos/ASIN/0937354465/qid=1108937525/sr=2-2/ref=pd_bbs_b_2_2/103-6123... "]ONE[/url]
a Christmas in February?
What about "the"? Do you count Christmase?
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Thank you Mister Micawber for your help.

Also, I would like to ask you what the article "a" means in the first sentence.

Would the second sentence sound better without "sackful"-genuine thanks for thougtfully selected presents.

Thanks again
I am only saying that when a person receives a lot of presents it feels like Christmas. However, I do not know whether to use or not to use an article before the word Christmas.
Your suggestion is to use "the", and Mister Micawber accepted "a" .
Now, I am completely confused.
Hello Spring

I think you can say "I didn't know there is a Christmas in February". Here "a" works as "another" or "a kind of" and "a Christmas" means figuratively "a season one can get a lot of presents". Similar usages of "a" are seen in: (1) "If Jupiter is a bit larger, it would have become a Sun" and (2) "But Thomas Edward Lawrence is not a Caesar or a Napoleon; he is rather an eccentric, flawed, reflective man of complex".


For your reference :[url="http://www.fsz.uni-hannover.de/Sprachbereiche/Englisch/dozenten/mcelholm/download/EN_ART.pdf"] McElholm's Lecture Note on English Articles[/url]
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Yes, I agree with Paco; 'the' does not work; either 'a' or no article is fine to express your idea. And yes, leave out the 'sackful'.