Well,
I though I did my investigation where I read that people can copy/paste articles if they mentioned the source of which I did.
But for example this article:
https://steemit.com/cryptocurrency/@danman1234/bitcoin-plunges-falls-through-4k
At the bottom i place the source link, but still it was not accepted, so now it is clear.
Do never copy paste articles from other websites fully, but just partly and always mention the source link.