The present-day English vocabulary grows very fast. Explain the

The present-day English vocabulary grows very fast. Explain the main sources of new words with examples.
【正确答案】:Generally, there are three main sources of new words. Rapid development of modern science and technology breeds new words like green revolution; social, economic and political changes bring about such words as fast food; the influence of other cultures and languages can be felt in such words as kungfu. (其他举例正确的也可给分)