How important is learning grammar when you are learning a language?
It depends, if you speak more not important that much, but if you use language for writing purposes - then really important.
maziausiai svarbi
very important
Not that important. You can learn grammar by reading/listening to stuff and deducing grammar rules from it. I think grammar becomes more important only at C1/C2 level.
Gramatika svarbu, bet manau, kad daug svarbiau žodynas
For me - it's very important.
very important
You have to understand how to use it, not just learn it by rote. But anyway, words and phrases are more important than grammar, because people will try to understand you by what (words/phrases) are you saying not how (grammatically correct).
As important as vocabulary.
It is equally important as all the other parts (but maybe a little bit less important than speaking, vocabulary skills).