"The country is Finland and the language is Finnish."
Translation:Maa on Suomi ja kieli on suomi.
Partitive is possible in this kind of sentence. If you are looking at a strange text, you could conclude: "Kieli on suomea" (This language is Finnish). On the other hand, in this case it says what is the name of the country and the name of the language (that is spoken in the country), and they shall be in the same (basic) form. Partitive is indeed a tricky case in the Finnish language.