different languages at the same time?
Do you recommend learn different langueges at the same time?
I don't. I think it is more efficient to add a next language after you get some proficiency with your previous one. Note that you'll still have to practice both (or all the three/four/etc.), otherwise you'll forget a lot.
You may also be interested in this thread: http://duolingo.com/#/comment/210742
Same opinion as olimo. Take them one at a time. Start with the easier one first :D, or the one that motivates you more, oooor if you have for instance french(just for e.g.) friends or access to a lot of french documentation/movies, do that one first.
It's always better to know 1 or 2 languages good enough to have a conversation than to know how to say the same 10 words in 10 languages if you know what I mean.
There are lots of people who successfully study more than one language at a time, but it is tricky, as Olimo said. Right now I'm experimenting with my duolingo lessons and find that some sequencing of studying is better than others. For example, Spanish and Italian are similar enough that if I study them back to back, my comprehension is improved but I make more spelling mistakes than if I space out the lessons or study German in between as a kind of buffer.
If anyone has good tips on developing multiple languages simultaneously, I would very much like to read about them.
I'm doing French, Spanish and German, but the first two are revision after years of disuse, whereas German I have never formally studied till now. It would probably be better for each individual language to study it exclusively, but I find this way more interesting. My keyboard is set up for Spanish, which comes in handy for some French speech marks, but is no use for German. Some vocabulary tends to leak between compartments in your brain, especially with the romance languages- i don't think I could so easily.handle Portuguese or Italian at the same time as Spanish.