Sometimes it’s easy to convince yourself that you know a word even though your actions demonstrate that this is not the case.
For example, imagine you are reading something in Chinese and you encounter a word that you’re 90% sure of.
You look it up in the dictionary ‘just to check’, and sure enough, it means what you thought it did and it’s pronounced how you thought it was, and you think to yourself ‘yes, I was right, I do know that word’, and so you keep reading, oblivious to the fact that actually you were wrong and you don’t know that word.
You might have learnt that word before, but you don’t know it because if you knew it, you wouldn’t have needed to look it up in the dictionary.
At this point you might protest that you did know the word, you just weren’t 100% confident that you were right.
The thing is though, for reading, confidence is just as important as knowing every other aspect of the word. If you are not confident about the word then you don’t know it well enough yet and would benefit from spending time studying it further.
If you convince yourself that you know words that you clearly and demonstrably don’t, you’ll never spend the effort required to learn them properly.
The next time you look up a word ‘just to check’ that should trip a mental trigger that you need to spend time studying that word, even if you ‘got it right’, to make sure you’ll be 100% confident of it in the future.
Maybe that means you spend a minute or two going over the word in your mind, paying attention to the parts you were not 100% sure of and telling yourself that you’ll be sure of them next time. Maybe it means adding it to a flashcard deck for further revision. Maybe it means both, or something else entirely. The important thing is to pay attention to any word you look up in the dictionary, regardless of how well you ‘know’ it, and spend some more time learning so that next time you won’t need to look it up.
Otherwise you’re not learning the word well enough to use in real life situations, and you’ll never be able to free yourself from using a dictionary.