Tongue twisters: 10 of the hardest tongue twisters for kids and adults in English - including Peter Piper

Many tongue-twisters seem like they're custom designed to throw you for a loop once you've had a drink or two, and now researchers say that vocal shifts in things like pitch and frequency during these tipsy attempts could serve as indicators of one's level of intoxication.

Dr. Brian Suffoletto, the primary author of a study conducted at Stanford University, said the experiment involved 18 adults aged 21 and older who were initially recorded reciting a tongue-twister... sober.

Following that, they were administered a substantial, weight-based dose of alcohol - enough to induce intoxication - and were then asked to recite a different tongue-twister each hour over the next seven hours.

The researchers also measured each person’s breath alcohol levels at the beginning of the study and every 30 minutes for up to seven hours. Using digital programmes, the researchers were able isolate the speaker’s voices and analyse measures such as frequency and pitch in one-second increments.

When checked against breath alcohol results, the researchers found that the model they developed was a good predictor of how drunk a person was - with 98% accuracy.

In a report for the Journal of Studies on Alcohol and Drugs, Suffoletto said the approach has a number of potential future applications, such as "a form of ignition lock on cars which would not allow someone to start their car unless they could pass the ‘voice challenge’."

Here are 10 of the most challenging tongue-twisters to pose to your friends, whether you're half-cut or not!

Peter Piper picked a peck of pickled peppers. How many pecks of pickled peppers did Peter Piper pick?

"Peter Piper..." is challenging due to rapid consonant repetition, testing articulation and co-ordination. It's particularly tricky as it demands precise pronunciation and quick transitions between sounds.

She sells seashells by the seashore. The shells she sells are surely seashells. So if she sells shells on the seashore, I'm sure she sells seashore shells.

"She sells seashells" challenges the reciter with alliteration and sibilance, making it tough to maintain clarity and speed. Tests the ability to navigate similar-sounding syllables rapidly.

Unique New York, Unique New York. You know you need Unique New York.

"Unique New York" tests enunciation and tongue placement, and is especially challenging for non-native English speakers, as it requires precise articulation to avoid blending the words.

Red lorry, yellow lorry, red lorry, yellow lorry.

"Red lorry, yellow lorry" presents a challenge with consecutive consonant clusters, testing diction and clarity. To see it written down suggests a simple task, but the HGV-based twister is difficult due to the quick succession of similar sounds.

Irish wristwatch, Irish wristwatch.

Another fiendishly simple-looking twister that will catch you off guard, "Irish wristwatch" is difficult due to the combination of "r" and "w" sounds, and tests tongue control and coordination. Pronouncing these sounds in quick succession can be challenging.

Six slippery snails slid slowly seaward.

"Six slippery snails" tests the ability to articulate the "s" sound rapidly, and is tricky due to the repeated "s" sounds in close succession.

Toy boat, toy boat, toy boat.

Another tongue-twister that seems simple on paper, "Toy boat" challenges with the rapid pronunciation of "t" and "b" sounds, testing co-ordination and precision. These sounds can be challenging to articulate in quick succession.

Fuzzy Wuzzy was a bear. Fuzzy Wuzzy had no hair. Fuzzy Wuzzy wasn't very fuzzy, was he?

"Fuzzy Wuzzy was a bear" presents a test for consecutive "w" sounds, which challenges coordination and clarity, while the repeated use of similar sounds makes it a true tongue-twisting task.

How can a clam cram in a clean cream can?

"How can a clam cram" once again presents a challenge with alliteration and the rapid transition between the "m" and "c" sounds. Another tongue-twister which is tricky due to the combination of similar sounds in quick succession.

A black bug bleeds black blood. What colour blood does a blue bug bleed?

"Black bug bleeds black blood" tests a person's articulation and coordination with the repetition of the "b" sound, and is difficult due to the quick succession of similar-sounding syllables.