Syndicating content?

If you are taking content, you need to seek permission unless it is public domain content.

Yes.

Whenever you take content from a site not designed specifically for that purpose, whose terms of service don't expressly allow it and set out the details of the permissions for using it, you can get into legal trouble.

In other words, you can take content from article directories (subject to their terms of service, which will always include taking the author's resource-box and active links with it: it's always explained, but it's always easy, too) because "taking content" is what article directories are there for. But rarely from anywhere else, without permission.

"Public domain" content (it doesn't mean "domain" like a "domain-name": it's a different use of the word and existed long before the internet) includes text whose copyright has expired (because the author's been dead for more than a certain number of years: for example Shakespeare, whose works are no longer copyright and are now in the public domain) and works which have been expressly put into the public domain by the author renouncing all his own rights to them (such as items on websites which expressly say "You can take this and republish it wherever and however you like"). But in all cases of doubt, always assume that taking content you didn't write yourself will be breaching someone's copyright and can lead to legal problems.

You surely need to get in touch with the original sites and seek prior permission to use their content.