Hello, I have noticed that many news sites use this link structure with folders: /numberofpost/keyword1/keyword2/keyword3/ example: http://www.url.ext/news/393751/0/britney/spears/song/ What do you think? Will this affect in rankings as all are like folder? Or its better /date/postname ? Thanks.
The keyword1/keyword2/keyword3 structure is wrong. It should be /news/393751/0/britney-spears-song/, which is much more useful.
Most of the news site use those structures like cnn: edition.cnn.com/2008/WORLD/meast/06/29/us.iran/index.html
all of these will work but as a rule of thumb you generally want your keywords for the page as close to the root URL as possible, example: www.yourdomain.com/keywords-go-here/
I also feel that this is the correct one: /news/393751/0/britney-spears-song/ More deep the URL will be more less chances will be there for that to be crawled
Always remember: hyphen is accounted more SEO-friendly than any other separator so first one is the best choice