"They celebrated the 100th anniversary of the declaration of the independence of the country."
Can I understand that "the" before "independence" is optional?
********** NOT * A * TEACHER **********
Snappy,
(1) I would
not use "the" before "independence," either.
(2) Your question reminded me that one of the most precious
pieces of paper in the United States is something called
The Declaration of Independence. As you know, the Americans
in 1776 declared independence from/of the United Kingdom. That is,
we respectfully asked the Mother Country to let us go out into the
world on our own. After a few years of unpleasantness, the United
Kingdom graciously granted our humble request.
(a) As far as I know, it would not be idiomatic to use "the"
in your sentence. For example, in 1876 we celebrated the 100th
anniversary of our declaration of independence. Our dear friend
France sent us the Statue of Liberty as a birthday gift.
(idiomatic = the way native speakers use the language.)
***** ONLY * MY * OPINION **********
P.S. But you would use "the" in a sentence like this:
I, Sir Charles Anderson, do now declare
the independence of
X-land from this day forward.