Tongue twisters are a great way to practice and improve pronunciation and fluency. They can also help to improve accents by using alliteration

2. Sheep
should
sleep in a
shed.

3. If two witches were
watching two watches,
which witch would
watch which watch?

6. Oh, What A to do
What a to-do to die today,
at a minute or two ‘til two;
A thing distinctly hard to say,
but harder still to do.
For they'll beat a tattoo at twenty to two
With a rattatta tattatta tattatta too
And a dragon will come when
he hears the drum,
At a minute or two 'til two today
At a minute or two 'til two.