
Bruce C. answered 06/29/20
Retired Technical Writer
The best way to expand your vocabulary is to read, read, and read some more. The best-read individuals usually have the broadest vocabulary, because they have witnessed countless examples of great words being used in their proper contexts, and their subconscious absorbs the subtle variations in meaning that result.
And not just any type of reading. You need to pick challenging - but well written - materials. By challenging, I mean that the vocabulary and sentence structure / grammar is at the top end of your reading level (you can take reading level tests online to determine your reading level). I stress well-written because you won't learn good grammar or sentence structure, or appropriate uses of words (vocabulary) if the material you read is not well-written.
You should read the great works of English literature for two reasons. First, many of these works will have vocabulary that is new to you and so this will move you toward your goal. But these classical works also are referenced in many more-recent works, and you will not fully understand the references if you have not read the classics. I also suggest reading works by well-known historical essayists and poets, because their works tend to contain a lot of unusual words, or words used in unusual contexts. Finally, read the speeches of some of our better orators - Lincoln, Kennedy, Martin Luther King, and others because they or their speech writers have turned out some truly well-crafted speeches that make wonderful use of a broad vocabulary.

Courtney W.
Bruce: that even includes the Bible and quotes in French and German! CW06/29/20