I never submitted article to article directory before. Couple days ago I tried to submit one article to an article directory on the web. I read the writer's policy (or something like that) and I couldn't find words that restrict writer to submit the article to another article directory, after article has been submitted there. So I visited other article directory (2-3 article directories), and I read the policy, and none words restrict to submit article in multiple directories. My question is still the same, is it ok to submit one article (it's the free article, writer is not paid) to multiple article directories ? Thanks before
Yes, it is perfectly fine, and quite normal, to submit your article to as many different directories as you want to.
yep, you should be able to do so. If the site says no, time to evaluate presence in the article site, whether should continue to be a member of site.
The only time that an article site would want exclusive use of your article would be when they pay you for exclusive rights to it.
If you submit one article with the identical contents, then Google can stick together weight of each article and will define them as duplicates of one content. Then will be applied Google filter - "Google Supplemental Results" or something like that.