Talk like a poetry book

“Oh,” said Phyllis, “my heart's thumping like a steam-engine—right under my sash, too.”

“Nonsense,” said Peter, “people's hearts aren't under their sashes.”

“I don't care—mine is,” said Phyllis.

“If you're going to talk like a poetry-book,” said Peter, “my heart's in my mouth.”

“My heart's in my boots—if you come to that,” said Roberta; “but do come on—he'll think we're idiots.”

“He won't be far wrong,” said Peter, gloomily. And they went forward to meet the old gentleman.

(E. Nesbit, The Railway Children)