... informal guides to what the French or the English really mean, when they are speaking their mother tongues, have been drawn up by other nationalities.

The guide also points out helpfully that when a Briton says “by the way/incidentally”, he is usually understood by foreigners as meaning “this is not very important”, whereas in fact he means, “The primary purpose of our discussion is...” On the other hand, the phrase “I'll bear it in mind” means “I'll do nothing about it”; while “Correct me if I'm wrong” means “I'm right, please don't contradict me.”

...

No less obvious is the fact that ideas about plain speaking do not travel easily across the Channel. As the Brits see things, a Frenchman who says “je serai clair”(which literally means “I will be clear”) should be understood as meaning: “I will be rude”. Also evident is the Anglo-Saxons' contempt for spectacular gestures à la française. The phrase “Il faut la visibilité Européenne”(“We need European visibility”) is rendered as: “The EU must indulge in some pointless, annoying and, with luck, damaging international grand-standing.” The British also suggest that the sentence “Il faut trouver une solution pragmatique” (literal translation: “We must find a pragmatic solution”) should be understood as meaning: “Warning: I am about to propose a highly complex, theoretical, legalistic and unworkable way forward.”

—Economist