As a film/media student i can confirm radio working is not really easy at all. You work long days, saying one wrong thing gets you fired, unless you're a bigger name you're basically stuck saying what producers want you to say, etc.
I'd imagine yea, you have to concentrate on how you talk so you don't stammer or studder or say "uh" alot
as well as think about WHAT you're saying too
Working long days isn't a problem though
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