I find that watching commercials in a foreign language (or in your native language if that's the target language) is very helpful since they are repetitive and use visual cues. Print ads are great too since you can usually guess a lot of the meaning. Also, try to carry something you can write with throughout the day. When you come across a word that would be useful to know in your target language, jot it down and make a point to look it up later. Also, make a point to read books whose authors use a lot advanced words. Personally, I like Anne Rice for her words and C.S. Lewis' Narnia books have a surprisingly high level of verbage for kids' books. Of course, it's hard to go wrong with old classics like the books of Shakespeare, Nathaniel Hawthorne, etc. In general, expose yourself as much as possible to your target language and use what you learn as soon as you can to communicate in the language. ---------------------------------------------------------- I'm sorry, I thought I did, but I did change my answer some in case you meant vocabulary in your native language. If this doesn't help, please let me know more specifically the problem you have with the answer.

Do the first thing that Allah commanded Mohammad to do. It's simple, requires no purchase, makes you more intelligent. READ!

Read, and whenever you come across a word you don't know, look it up. I have a dictionary at all times in my purse for just that purpose. After time, daily new words add up to a bigger more functional vocabulary.

How can you increase your vocabulary with medication? Anyway, try reading. That should help a lot. There are also vocabulary podcasts that are okay. I would recommend studying etymology, it'll help you understand how words are formed and how they are related, so it's easier to retain and even make up new words!