I find English and French much easier I don't have to think when using them. German on the other hand.. it's a very complex language and the similarities with the dutch language makes it all the more difficult..
Spanish, German or French.
You don't need to study Spanish and Italian or vice versa. Learning one becomes piece of cake after learning the other, I'm told.
That is, considering the career purposes. Mandarin Chinese gets an option in that regard too.
For pleasure I'd go Greek, Persian or Finnish.
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