Lexis: active and passive

I'm reading a marvelous book called Learning Teaching, by Jim Scrivener. This book was recommended to me by one of the greatest people I know, and it's absolutely a must if you're interested in language teaching. Here are a few things I have found interesting from the learner perspective:

Lexis

One of the most useful observations in the book is about the concept of lexis. Lexis is all the words, collocations and phrases that compose a language. These parts of language fall into two big categories, active and passive. This means that we have some words we use all the time, and others that we don't use often (or ever) but know and can recognize.

Active vs. Passive Lexis

An example of this in my case would be a word like "microscope". I never use this word! but I know what a microscope is, so if I read or hear this word, I understand it. I think it's accurate to say that the majority of my lexis is passive. I know a huge number of words and expressions, but I only use a very small number of them on a daily basis. This is true in my native language, and it will also be true in any language I learn. What do you think? Is this true for you? What percentage of all your native words and expressions do you use on a daily basis?

Learning Strategies

The value of thinking about active and passive lexis when you're learning a language is that you can classify new vocabulary, and this will probably affect your strategy with learning. You need to have a good active vocabulary which allows you to communicate in everyday situations. This vocabulary should be accessible and increasingly automatic for you. So you may need to put in some extra effort here if you can't remember the words and expressions. But as you continue, you'll also be learning a lot of passive lexis. It makes sense to pay attention to this, and connect it to your active lexis when you can, but also not to worry too much if you have trouble remembering all the words. When you encounter new lexis, it may help to ask, active or passive? For a scientist, "microscope" is probably active!

Why Is Passive Lexis Important?

As you learn, you'll naturally increase both your active and passive lexis, and your passive lexis will be important, especially when you're reading or listening to other people speak. In fact, increasing your passive lexis may be one of the most important elements in understanding what you hear, so using resources like TED and the BBC can be very helpful. You may never have occasion to say "at sixes and sevens," but if you know what it means, you'll undertand it when someone says it!