As far as I know, both "Lei è diventata donna" and "Lei è diventata una donna" are acceptable.
But sometimes the article is not optional. Is there a general rule with omitting article?
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Sign up to join this communityAs far as I know, both "Lei è diventata donna" and "Lei è diventata una donna" are acceptable.
But sometimes the article is not optional. Is there a general rule with omitting article?
The "articolo indeterminativo" (un, uno, una) is different from the "articolo determinativo" (il, lo, la, i, gli, le) in that it tends to indicate one (any) among many, while the latter tends to indicate one (specific) among many.
In this particular case there is no formal difference in the two usages. The only case where there is a difference is when you promote the noun to a capitalized one, to dignify the concept to the more abstract one: "Lei è diventata Donna", is used to indicate that she has developed those traits typical of an idealized woman.
In this case, you cannot use the "articolo indeterminativo", because that cannot be used with capitalized nouns, nor you can use the "articolo determinativo", because we are talking about the concept of woman, not an instance of woman, and therefore you are forced to drop the article completely.
When you use the article, "donna" is a noun, as in "Lei è diventata una statua"; without article, it can be intended as an adjective, as in "Lei è diventata bionda". The sense of the phrase is slightly different, if you use the article the change is perceived as stronger, more radical.