"Warsaw is a European city."
Translation:Warszawa to europejskie miasto.
Hmmm... usually the adjective that just describes the noun goes before the noun. But with this particular phrase... I guess it's ok. But it emphasizes the "European" part. Like "Warsaw is really a big, European city with big, European lifestyle", blablabla. Added, anyway.
In what situation is it "to" and in what situation is it "jest" and in what situation is it "to jest"? Dzieki!
In most situations, both "to" and "jest" are perfectly fine. You just have to remember that after "to" comes Nominative, and after "jest" Instrumental.
"to jest" is also correct, I guess, but to me it seems a bit strange and rather unusual. I think we generally don't accept it unless someone asks specifically.
You can take a look here: https://www.duolingo.com/comment/16373167
"europejskie miasta" (no capital letters for adjectives) is plural Nominative or Accusative.