Which is correct?
Ich lerne Deutsch.
Ich lerne Deutsch
In any simple sentence like this you can count on the verb being in the 2nd position (the second word) of the sentence.
none of them. Ich lerne Deutsch or Ich lerne die deutsche Sprache
Ich lerne Deutsche would mean "I learn German people" :)
When I found out that I was to be stationed in Germany, I bought a book called ich lerne Deutsch.