Literary Allusions to Folk Tales

Shakespeare, King Lear:
“Fie, foh and fum,
I smell the blood of a British man”

Original:
“Fee-fi-fo-fum, I smell the blood of an Englishman, Be he alive, or be he dead I’ll grind his bones to make my bread”

The BFG:
The dream the BFG gives to the Fleshlumpeater gives him nightmares of Jack, the giant killer:
“Jack is the only human bean all giants is frightened of. […] They is absolutely terrified of Jack. They is all hearing that Jack is a famous giantkiller”.

Task: What is the impact of the allusions to Jack and the Beanstalk? Why do you think the writers have chosen to make them? What are they trying to imply about characters?

please help anyone