Client: "Im afraid I have to teach you a small lesson here, your email to management contains a non-existent word"
Me: (looking at email, very puzzled) "I cant see any incorrect words"
Client: "this word 'en masse' doesnt exist"
Me: "sure it does, it means all at once, look at http://dictionary.reference.com/search?q=en+masse"
Client: silence ....