"You must not commit more crimes!"
Translation:Du får inte begå fler brott!
Just wondering when måste would be used and when får is acceptable?
Can you say "Du måste inte begå fler brott?
Saying "Du måste inte begå fler brott" is pointing out a fact: "You (really) don't have to commit more crimes". Saying "får inte" is more equivalent of "must not".
I was curious about "fler", "flera", "mer" and "mera", found this: http://www.thelocal.se/blogs/theswedishteacher/2011/01/24/mer-mera-fler-or-flera/
"Fler" and "mer" is the way you should write it (of course you can say it too). If you speak you can use "flera" and "mera".
The word "måste" is like "must", something that you have to do. So "måste inte" means that you don't have to do it.
As an auxiliary verb, får means that you "get to" do something, which in this sense means that you have permission to do it. So "får inte" means that you don't have permission to do something.
Even thought the literal translation of individual words would suggest using "must", the meaning of the English sentence requires that you use får.
Is får modal here and hence begå is infinitive? I continually misapply the present tense ending. The sentence "Vi begår alla brott ibland" uses the present tense but I can't distinguish why. Any suggestions on how to test?
få in the sense of "may" is always a modal. It's just that it can mean "receive" as well, in which case it's a different, non-modal verb.
The second sentence works just the same as in English: "We all commit crimes sometimes" - just the v2 rule dictating that Swedish move the verb one step, so that it takes the second position.
If this sentence means you MUST not, then how would one say, "You may not"?
This sentence may have been a mistake, since we're aiming for US English specifically. In UK English, "you must not" and "you may not" are the same thing here. If you want to be strict about "you must not", it would be du måste inte, and "you may not" would be du får inte.