New memories are formed when we experience two things together. A mother holds up a ball in front of a child's face and says "do you want to play with the ball?". The child sees the ball, and hears the word "ball", and the brain stores these two things together.

So, to learn vocabulary or a new piece of language, we must simultaneously focus our attention the two factors that are most important about language. These are:

• the sound (pronunciation)

and

• the meaning (context, situation, story)

These two things correspond to the areas in the brain which are activated when we use language. They are are which process phonology, and semantics.

A child doesn't have to do this actively think about meaning, because a child always experiences language in context. The brain automatically stores together the sound with the situation in which it experienced the language, because the semantic and the phonological parts of the brain were activated simultaneously.

So when we learn language, we must actively focus our attention on the meaning of the language and the sound at the same time.

Brain cells which fire together, wire together.

When we read a story we can relate to, it activates the semantic part of the brain (=the context) because we are familiar with the situation. Once we have activated the meaning in our minds, we focus our attention on the sound of the language to enable our brains to store these two things together. Duolingo doesn’t connect us to anything in reality and so fails to properly activate the semantic centre in the brain. Gamification tells us we are learning, but it is an illusion. We are not activating the meaning of the language in our brains.

The monkey drinks the milk.

Sentences like these are not connected to any reality, and so our brains just ignore them because the semantic area is not activated.

Would you like milk with your coffee?

I can easily imagine a context in which I would use this sentence, so the meaning is activated in my mind. Duolingo uses some sentences like this, but if you experience 10 sentences in 10 different contexts in 6 minutes, your brain is going to struggle to really activate the context and meaning. You're better off reading a book such as a graded reader which remains in the one context for the length of the book.

Decontextualised language doesn't stick. Duolingo is decontextualised, so it doesn't work.

What we can learn from my mother

My mother is reading an A1 book in German written for German learning teenagers. She is working with the audio to ensure she can also pronounce the words accurately.

There is a sentence:

“Simon holt Laura am Bahnhof ab. Laura möchte nicht sofort nach Hause fahren, sie möchte ein Eis essen und sie gehen in ein Eiscafé”.

There were some new words here for her: möchte, abholen, sofort, and Eiscafé.

She now knows what these words are in English because she translated them, so she can reread the sentence again and again and immediately know what it means. Whenever she sees/hears those words in another context, her brain is going to recall the situation in this book, and she will have direct access to the meaning of the word, as opposed to first accessing a translation of the word in her mind.

If she had "learned" those words in Duolingo, her brain would first have to translate the words to English, which is the language the meaning is connect to, and then back from English to German before she is able to produce the language. This is too slow.

Do this instead of using Duolingo:

• Collect language in a notebook or on your phone and read over your notes regularly. This reminds you of when you found the language and reactivates the meaning in your mind.
• Go over your class notes again on different days and activate the sound of the language and think of the situation you were talking about.
• Use graded readers to study with, listen to the audio and pay attention to useful language.After a few times reading a section of the book, close the book and try and listen and follow along without reading. Then stop the recording randomly and try and repeat word-for-word what you just heard. If you can’t do it, go back and start again. This sequence activates meaning and sound.
• Have conversations with Chat GPT about your life, asking it to correct you. Talking about your life activates the meaning in your brain. Then copy the conversation into a text-to-speech tool like Speechtexter and listen along without reading, activating the sound. Print the conversation and read it again a week later.
• Take active control of your language learning, ensuring input language is related to your life as much as possible. Do not use vocabulary lists and do not learn from random, decontextualised examples. The brain will only remember once sound is connected to meaning (i.e., your reality). Regularly read aloud activating the sound of the language.
  

All of these strategies will be much more effective at activating the sound and the meaning in your mind than apps like Duolingo ever will.