The only examples I have found are in English and along the lines of "The 'Lord' in 'Oh, Lord --' is in vocative but doesn't differ in any way from the nominative". In what languages does it differ (and how, obviously)? In what kind of situations is vocative used in these languages? Is not using vocative seen as an error or an insult? Is globalisation changing the way vocative is being used?
And the future tenses. I ran into a mention that in some languages there are several future tenses. As a native speaker of a language with no future tense, I'm bewildered by this. I can understand needing one future tense, but several? I'm assuming one is for near future and the others for various degrees of distant future (since that's the first logical explanation I can think of, but I do lack imagination, so...). How are they used in relation to other tenses? Do they also indicate the propability of something happening or just the time frame it's expected to happen in?
Thank you in advance! I know these both differ in different languages, so I'm interested in hearing of any languages having eithe of these features. Even it helps if you can mention a language that has either, since that'll give me at least something to google.
ETA: Thanks, everybody! You helped me a lot!