As a non-native English speaker, I wonder: what's the story behind using umlauts in the word "coöperating"? Never seen it before.
"Nowadays in English, the diaeresis is normally left out (cooperate), except by The New Yorker, or a hyphen is used (co-operate). It is, however, still common in loanwords such as naïve and Noël."
This made me smile. Thanks! :)
The New Yorker does it for all doubled vowels that aren't pronounced as long vowels.