Having a great English vocabulary doesn't just mean that you can understand lots of words and phrases: it also means that you can use these words and phrases and that you can remember them when you need them.
This is the difference between an active and a passive vocabulary. Generally, most people's passive vocabulary is far bigger than their active vocabulary, and the secret is to try and "activate" passive knowledge.
There are a number of ways that you can activate your passive vocabulary in English, ranging from simple five-minute activities to longer periods of study. Most activities work best if a) you have a good dictionary and b) you keep a vocabulary notebook.
Good English dictionaries
A good English dictionary should be up-to-date (no more than five years old!) and should be easy to understand. Make sure that the definitions are written in clear English. Pictures also help you to understand some words. I strongly recommend the Longman range of dictionaries, as there is good coverage of spoken and written English, British and American English, as well as clear example sentences.
Vocabulary notebooks
When you come across a new English word or phrase, make a note of it! Look up the meaning in the dictionary, making sure you are aware of any grammatical information. (For instance, if you are looking up a verb, check to see if the verb can be used in a passive form, if it is followed by any particular preposition, and so on.) Check also for the pronunciation and use of a word. Is it particularly formal or informal, or used in certain word partnerships? For example, we say "do housework", but "make an effort".
When you find a new word, check to see if you can use it in other ways. English is a flexible language – nouns, verbs and adjectives often share the same stem. For example, a house, to house, housing policy, and so on.
When you write down your new word in your notebook, try to include an example sentence in English.
Some people find it helpful to organise notebooks into themes. So rather than having a list of words without any obvious connection, you divide your notebook into themes, with one page containing words to do with the house, another page with words to do with jobs, and so on.
1. An English word a day
Choose a new word or phrase from your notebook and try to use it as often as possible in one day. Think of situations where you would need to use it, and write down a couple of example sentences. Go back to this word or phrase after a week, to make sure you still remember it.
Some people find index cards useful. You can write down the word on the card and carry it around with you for a day, taking it out of your pocket whenever you have a moment and trying to put it into a sentence.
2. Review
The next time you have a spare couple of minutes, flick through your notebook. You'll be surprised how much comes back to you! Choose a page where you have already stored a number of words and expressions, cover the page, and try to remember what you wrote. Then look at the page and see how many you remember.
3. One word at a time
When you read a page of a book or newspaper, decide you will only look up one word in a dictionary. When you write it down in your notebook, also make a note of any synonyms (words that mean the same) or the opposite of the new word.
4. English word building
Take a prefix (such as "en", or "pre") and make a list of all the words that can follow. (For example, encircle, enclose, enlist; prenatal, premature, pre-war.) Here are some more prefixes you can use:
dis, il, im, ir, pro, anti, de, un, con, re
1. Read
Read something that interests you. It could be a newspaper, a novel, a magazine, or even an English graded reader (a simplified book). Working page by page, underline the words or phrases that you don't know. Look up only those that are important for understanding, or which are repeated. Use a good dictionary, and make a note in your English vocabulary notebook.
2. Blitz
Focus on a theme, such as sport. Divide one page of your notebook into three columns. In the first column write down as many sports as you can think of. In the second, write down all the equipment you need for the sport. In the third, write down the scoring systems. You might end up with something that looks like this:
tennis racquet, ball, net umpire, love, linesman
football pitch, ball, goal posts referee, offside, penalty
You can use this method for many different themes: houses (rooms of house, furniture, styles); jobs (names of jobs, places where these jobs are done, characteristics of the job) and so on.
3. Word association
Write a key word in the middle of a page and draw a bubble around it. Then draw lines out from this word connected to smaller bubbles. In the smaller bubbles you can add words associated with the main word.
For example, you could write "email" in the middle of a page. Then the smaller bubbles could contain words such as "write", "compose", "receive", "delete", "reply" and so on.