There's nothing worse than WANTING to use a particular English word... and KNOWING that you know the word; you've studied the word... but you just can't think of it at the moment. It's really frustrating!
Why does this happen?
Why is it so hard to bring words to mind when you need to use them?
The answer is related to...
Active vs. passive vocabulary
Your passive vocabulary includes words that you can recognize and understand if you see them, or if someone else says them to you.
Your active vocabulary is the words that you can understand AND use yourself.
And to be noted that this has nothing to do with "active voice" and "passive voice" in grammar. It is a completely different concept.
Most people have a bigger passive vocabulary than active vocabulary. This means you can understand better than you can speak. You know a lot of English words, but you feel like you don't have enough vocabulary to express yourself fully.
So how can you turn your passive vocabulary (words you recognize) into active vocabulary (words you can use)?
To remember new words better, USE them right away!
Every time you learn a new word – for example, from an English lesson or article – write it down in your vocabulary notebook. Writing is more ACTIVE than just reading a definition.
I suggest writing down:
The word
The definition in English (or translation)
1 example sentence from the article or dictionary
1 example sentence that YOU create
Here's an example:
Imagine you just learned the word “generous.” Write in your vocabulary notebook:

WORD: generous (adjective)
DEFINITION: when a person gives time / money freely
EXAMPLE 1 (from the article):
“Thanks for paying for my dinner. You’re very generous.”
EXAMPLE 2 (my example):
“My brother is generous because he gives a lot of his money to charity.”
It’s best if your example sentence is true or relevant to your life, because this creates a personal connection with the new word. This helps you internalize the vocabulary.
The next day, read your vocabulary notebook again and try to add one more example sentence using the new word.
The strategy of "using new words right away" and creating your own example sentences is something you can do at ANY level of English - from beginner to advance.
If you make this a habit, then you'll find yourself with a much larger "active vocabulary," making it easier to speak and write in English without going crazy trying to think of the word you want.
VOICE Research and Training Institute is the brain child of KALVI Higher Education and Research Institute, Madurai, South India with the expertise and knowledge to empower learners in the communicative skills of the English Language running through the Industrial Hub of a community that influences a country at large.
VOICE with a penchant desire to reach the seemingly unreachable heights in the arena of communicative English, has developed innovative and result oriented training material to equip the teaching and the learning communities. The ability to express one's versatility in the language is the gateway that opens up to a global treasure trove.

For more info https://voiceskills.org/