If you could give up the language of your home country/ where you live in exchange for the ability to fully comprehend/speak/write three other languages would you do it? By giving up your knowledge of the language where you reside, you would now be unable to comprehend that language at all, except for the most minuscule and simple terms and this would essentially last you until the day you die. Also, although you will be able to fully comprehend and write three other languages of your choosing, you aren't getting any free money so if you don't have enough cash to move countries and you take up this deal, well GL. For more exciting purposes, let's add that you are only presented this question one time, and you must answer on the spot knowing you will never have this same opportunity again.
Personally living in america, I'd take this deal. Giving up my knowledge of english, I'd take spanish, dutch and (of course) japanese. No idea what I'll do about my job, but seen plenty of people that get buy without knowing any english so hopefully I'd make it.