Elizabeth, Elspeth, Betsy and Bess

Elizabeth, Elspeth, Betsy and Bess,

They all went together to seek a bird's nest.

They found a bird's nest with five eggs in,

They all took one, and left four in.*

* "Elizabeth, Elspeth, Betsy and Bess" refers to one person since all of those names are diminutives of Elizabeth. That's why all four were able to take one egg, yet leave four in.