Do you have a telephone voice? It’s the voice you use with strangers on the phone when you speak clearly, softly, and use very polite words. Now, compare that to the way you speak to your best friend. You’re probably more direct, faster, and use lots of informal vocabulary. The fact is we all change our language depending on where we are and who we’re speaking to. But for one group of people, the choice is much greater. Bilingual speakers can choose to use a range of vocabulary from two different languages.