>>487 Ruby
str = <<~EOT
Alice was beginning to get very tired of sitting by her sister on the bank,
and of having nothing to do: once or twice she had peeped into the book
her sister was reading, but it had no pictures or conversations in it,
'and what is the use of a book,' thought Alice 'without pictures or
conversations?'
EOT

puts str.gsub(/(?<=\b\w)\w*(?=\w\b)/){|m| m.chars.shuffle.join}
#=>
Aclie was bngneniig to get very terid of sntitig by her seistr on the bnak,
and of hnvaig nnthoig to do: ocne or twcie she had ppeeed into the book
her sitser was rniadeg, but it had no piteucrs or cinsoentravos in it,
'and waht is the use of a book,' tohught Aclie 'wtihuot pricetus or
coenrovanstis?'