[MaximillianII]

Speaking foreign languages opens truly opens many opportunity that most monolinguals (especially English-speaking ones) do not even suspect. Yes, my German colleagues and friends all speak English and we could get along fine using it. However we wouldn't be able to share our personalities and cultural differences as well as we do on a daily basis if we didn't share a native language (for them) spoken at a high level (for me).

[copsarebastards]

It's not even just an opportunity thing. Becoming fluent in Spanish has really changed the way I think, particularly on political, social, and emotional issues. Spanish is really preferable for expressing many ideas--it has a richer vocabulary for certain topics and forces word patterns that encourage different ways of thinking. Thinking in Spanish changes not only how I think, but what I think. Being able to think both ways gives me the ability to approach problems from more directions.

[Dewie3]

People in general seem to underestimate how important it can be to speak the same language as a group[1], even when you happen to share another language. If I were to move to another country for many years, I would definitely start learning the most relevant language there. Even if ~98% spoke English.

Being able to speak something like English in some part of the non-English word might make you able to communicate with people there. But that doesn't necessarily mean that you'll be able to have meaningful connections compared to speaking the native tongue.

[1] Like the native language in some country or region.

[thfuran]

If you can't form meaningful connections when you're speaking your native tongue and they aren't, why could you when they are and you aren't?

[Dewie3]

Maybe I'm just bad at it.