Some of these words and phrases can be hard to use correctly, since the meaning is so subtle and slight. You may sound like you are slurring or mumbling. You will learn strategies such as speaking in shorter sentences, and control your breathing and the rate of your speech.
Master the use of filler words and you will be sounding like a native speaker in literally no time. Recent research at Columbia University suggests another reason.
They're often used in lieu of pausing and are closely connected with hesitation in speech. If the purpose is to grab a moment to think, we should allow ourselves to wonder: Why are filler phrases needed at all?
Make a list of commonly mispronounced words, and practice saying them into a tape recorder before the interview.