A simple children's verse, a more sophisticated children's verse, and the first verse of an adult poem, Thomas Gray's "Elegy written in a country church-yard"

Mary had a little lamb,
Its fleece was white as snow,
And everywhere that Mary went,
The lamb was sure to go.

Three blind mice,
Three blind mice,
See how they run!
See how they run!
They all ran after the farmer's wife,
She cut off their tails with a carving knife,
Did you ever see such a thing in your life,
As three blind mice?

The curfew tolls the knell of parting day,
The lowing herd winds slowly o'er the lea,
The ploughman homeward plods his weary way,
And leaves the world to darkness, and to me.

You can find out more about those on Google if you want!