Communication skills will improve only when you are strong in your vocabulary and when you have good command over a language. To improve your vocabulary, read a lot of books, newspapers and watch a lot of news channels. To increase your fluency, try to converse in that particular language with people who are well versed I it. It may be a little difficult in the beginning but as days progress you will master it. Be bold and confident. Don't let shyness be a hindrance to your progress.