The story of the shepherd with the talking sheepdog

The shepherd said to the sheepdog, "I've got some sheep in the valley. Will you go and round them up and put them in the pen?"

And the dog went, "Alright."

And he went away and came back an hour later. And the dog went, "I've done it."

And the shepherd said, "How many sheep were there?"

And the dog went, "40."

And the shepherd said, "That's strange! There were only 38 this morning."

And the dog went, "You said 'round them up'!"

(Source: Duggie Brown, "Act Your Age", BBC Radio 4, Wednesday 23 May 2011)