How does it only take a year or so to speak/understand our first language but it’s so much harder to acquire another language?

Question

Like, we have a frame of reference (first language), so why is it so hard to learn another language after that?

In: Other

Answer 1

Pretty much half of these comments are just wildly wrong or speculative.

The basic reason is that our brains are pretty lazy. If you already know a word for something, it is increasingly hard to convince it to learn another one. As the association between the words and concept becomes stronger, the difficulty of picking up new language for that concept increases. Repetition is pretty much the only way to learn, but the increased adversity to repeating makes it harder and harder to learn.

I give you a cookie every time you say “please” for a year. Then, the next year I tell you that I will give you a cookie every time you say “por favor”. I will still give you a cookie if you say “please”, but will also if you say “por favor”. You have very little incentive for saying one over the other, so why bother with the new one?