Снова, опять, вновь, ещё раз
What are the differences in meaning and usage? Are they largely interchangeable?
I'm sure I saw discussion of this before, or at least снова vs. опять, but I couldn't find it again.
Thought about your question for an hour before going to sleep :)
There are no strict rules for using that words, they are slightly different in there styles, but in many cases you can use all of them. I'll try to provide some examples.
Вновь is more 'book-style', so it's not so widely used in common everyday speech. In general, 'снова' is a correct everyday replacement for 'вновь'.
'Еще раз' used more often at the end of the sentence - 'Можешь повторить это еще раз?' (Can you repeat it once again?). Actually, 'once again' - is the closest translation. Or sometimes we can put 'Еще раз' to the beginning, let's say 'Еще раз, ты пойдешь на вечеринку?' - here it means 'Let me clarify, are you going to the party?'.
'Снова' and 'опять' - closest translation is just 'again'. Usually used in the middle of the sentence, right before the verbum. 'Я опять играл ночью в варкрафт' (I played warcraft in the night again). You can also use 'снова', it doesn't matter.
Опять and снова actually have a slight difference. Снова is more positive "again", while опять has more negative sense. Examples:
- Наша команда снова победила! - Our team won again! :-)
- Наша команда опять проиграла... - Our team lost again... :-(
And as Larisa_L mentioned here about the joke "не опять, а снова":
Mother to her child:
- Расскажи мне стихотворение. Ты должен повторить его. - Tell me the poem. You should repeat it.
- Опять??? - (negative) Again???
- Не опять, а снова! - Not (negative) again, but (positive) again!
There is also a joke in Russia. When something annoying is happening again, and then someone asks - What, again? Опять? - they often get an answer - Не опять, а снова? (Not again, but again) As if there was a difference between the two, while there is actually none.
Some addenda: 1. Вновь can mean "недавно, в последнее время" and is a part of the commonly used phrase "вновь прибывший" - someone who just recently arrived.
- Think of "еще раз" simply and literally as "one more time"