system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When you're learning a new language, you translate every word back to you mother tongue in your head. But when you've mastered the language, you don't need the translation anymore. How does this work?

I often watch television without subtitles with my mom, and she sometimes asks me to translate the difficult words or sentences. But since a few years I have had difficulty trying to come up with the right translations, and especially after I studied in an English speaking country. I know exactly what the words means, can describe it, and can think of synonyms, but have trouble with finding the right translation in my mother tongue.

I lately realized that I don't need to translate English in my head, and was wondering if this causes the trouble with translating.
So how does this work? Is your brain just translating it so fast you don't notice it? And if so, where does the trouble with translation of words and sentences in my mother tongue come from?
gpt
Words are a kind of symbolic algebra. When you really learn a word it is a natural meaning. The word represents a native thought.

So when you think the word "cat" it evokes a series of ideas. Furry. Small. Sharp. whatever... Whether you like cats or hate them the word itself evokes and invokes the the ideas and images as a primitive.

So then you start to learn a second language. You learn "gato" is "cat, but in spanish". It's an indirect. It's a step away. You have to turn gato into cat. And you have to turn cat into gato. Each in terms of the direction... new to native or native to new.

Eventually, with familiarity, you stop thinking "gato is cat in spanish" and so gato directly invokes the same things as cat. Furry. Sharp. Small. The two words are proper synonyms. Neither has primacy so both are equally available.

At that point the "is versus are" translator is in charge. You know when to use the word "is" and you know when to use the word "are" based on context. Both have the same meaning, but one is slightly more correct than the other depending on what other words are around it.

Further, in some languages there are unique verbs or tenses or whatever. In one languages it takes one word while in another it takes two. But the same thing eventually happens.

So just like you can learn to use a fork as a spoon or whatever, the interchange of tools, once you can use both tools, is just a context and technique issue.

So basically the difference is naturally-accessible versus takes deliberate thought.

Once something is naturally accessible to your brain then it's naturally accessible to use.

Language is just a tool at some levels. It's an inherent means of information at another. But the brain is incredibly plastic. So the change is a result of that plasticity.