How can I expand my vocabulary daily?

Answer of René Alix, natively fluent in English From Quora

The problem with most advice to this type of question (including the advice in the answers to this specific question) is that it does not distinguish between active and passive vocabulary, nor between receptive (reading, listening) and productive (speaking, writing) aspects of language.

You will acquire lots of new words from reading, sure. And from watching television and movies and Youtube videos. And from listening to songs and poetry and anything native speakers might be saying. But for the most part those words will solely remain in your passive vocabulary. After seeing/hearing the same words a few times and figuring out their meaning from context, you will usually understand them if you encounter them again. You might, however, also be hampering their acquisition if you don’t really figure them out solidly from context, but you’re just haphazardly guessing. You need to create definite associations for a word in your mind to retain it at all. So that’s the first step — make sure you do really understand the new word. Look it up in all its different contexts.

But even if you retain words, you won’t automatically be able to use them in speech and writing. For that to happen, you need to move new words into your active vocabulary, by producing them yourself repeatedly instead of just taking them in passively.

Once you are reasonably fluent in a language, your primary problem with acquiring new words is that your vocabulary is good enough to understand most of what you come across, and you can communicate well enough, and so you no longer use the methods you used when you first studied a language — you take in everything by osmosis. That works well enough, it is after all what native speakers do themselves. And those early methods can be tedious; people are usually glad if they can leave them behind.

But native speakers also have a huge gap between their active and their passive vocabularies. If you want to improve, you need to press some of those old methods back into service. Such as flashcards, and repeating after native speakers.

I’ve long since become natively fluent in English, but I still enjoy increasing my active vocabulary because being able to express nuance is cool. When I come across a word that I don’t know, I mark it, and look it up after I am done with the text. I use the digital equivalent of flashcards (Anki) and add the new word and context into my rotation if I decide this is a word I would like to use actively. Not all words are worth incorporating — there are too many words in total, and I have little use for obsolete ones, for example, or for jargon in fields that are not within a domain that interests me. I set up Anki so I have to type the new word each time it comes around. I also have a notebook in which I practice writing the new word in context, and I try to use it in general conversation several times each day that it pops up in the rotation. I memorize words better if I write them by hand than if I just type them. I also read the sentences I create out loud, and I make little speeches that include all the new words I am learning on that specific day. Yes, I talk to myself a lot. I don’t care whether anyone thinks I am nuts; this is pretty much a polyglot’s life. Since Anki handles the spaced repetition by itself I don’t have to do anything else; I will eventually know the new word well enough to produce it on demand.

I’ve got a prodigious active and passive vocabulary, so this method works for me.