Learning to speak well is a key element of building a successful career. Nothing kills communication as effectively as the listener or listeners not being able to understand the person speaking.

If the person speaking is mumbling, "swallowing" parts of words or even entire phrases, or speaking so quickly that words and sounds are getting jammed together, it becomes difficult to hear what they are saying. The speaker might as well be speaking a foreign language for all the listener is getting out of the conversation or presentation.

And while mumbled or slurred speech can be caused by various physical impairments or medical conditions, such as stroke, often the culprit is just sloppy speech. The speaker is overexcited or just has a habit of speaking in a particular way.

Breaking Habits

Any habit can be broken, and the first step to cleaning up sloppy speech is being aware of how you speak. Once you're aware, you can practice speaking well. Tongue twisters, sentences that repeat similar sound patterns, are an excellent vehicle for this because trying to say them aloud forces you to pay attention to how you're speaking. To say a tongue twister properly, you have to concentrate on what you're saying and fully enunciate each word and syllable—otherwise, your words are going to get all twisted together into a garbled, meaningless mishmash.

Below are several sets of tongue twister exercises for you to practice speaking clearly and enunciating properly. Once you've learned them, try saying several tongue twisters before your next important conversation or speech. Your focus should carry over, and you'll be speaking more clearly than you would have otherwise.

Tongue Twister Exercise Set 1: Basics

Say each of the following sentences out loud three times each, as quickly as you can while fully enunciating each word.

Keeping customers content creates kingly profits. Success seeds success. Bigger business isn’t better business, but better business brings bigger rewards. Wanting won’t win; winning ways are active ways. Seventeen sales slips slithered slowly southwards. Don’t go deep into debt. Ensuring excellence isn’t easy. Time takes a terrible toll on intentions. Feel free to follow that fellow. Old bones groan when wind moans.

Tongue Twister Exercise Set 2: Classics

Here are some familiar, moderately difficult classics. Say each of the following sentences out loud three times each, as quickly as you can while fully enunciating each word.

She sells seashells down by the seashore. If Peter Piper picked a peck of pickled peppers where's the peck of pickled peppers Peter Piper picked? A flea and a fly flew up in a flue. Rubber baby buggy bumpers. Fuzzy Wuzzy was a bear. Fuzzy Wuzzy had no hair. Fuzzy Wuzzy wasn't fuzzy, was he? How much wood would a woodchuck chuck if a woodchuck could chuck wood? Susie’s sister sewed socks for soldiers. I scream, you scream, we all scream for ice cream! I wish to wish the wish you wish to wish, but if you wish the wish the witch wishes, I won't wish the wish you wish to wish. Betty bought butter but the butter was bitter, so Betty bought better butter to make the bitter butter better.

Tongue Twister Exercise Set 3: Challenge Set

Don't be fooled—it's not the length that makes a tongue twister challenging (although a few of these are fairly long); it's the particular combination of sounds that makes them so tricky. Have fun!

The sixth sick Sheik's sixth sheep's sick. An ape hates grape cakes. A tutor who tooted the flute tried to tutor two tooters to toot. Said the two to the tutor, "Is it harder to toot or to tutor two tooters to toot?" These thousand tricky tongue twisters trip thrillingly off the tongue. Six thick thistle sticks. Six thick thistles stick. Pad kid poured curd pulled cold.* Top chopstick shops stock top chopsticks. Of all the smells I have ever smelt, I never smelt a smell that smelt like that smell smelt. Black bugs blood. We supply wristwatches for witchwatchers watching witches Washington wishes watched.

Repeat any or all of these exercises as many times as you like, and see how quickly your enunciation improves.

*According to MIT researchers in Boston, this is the world's hardest tongue twister. When asked to repeat the phrase 10 times quickly, many volunteers were forced to stop talking altogether.