What does "leave in French" mean?
Interested in your question. Everyone knows what it means to "leave in English" - it means to leave without saying goodbye. And the British in such cases say "to leave in French." The meaning is the same.
It is like tea with milk, we consider an English tradition, and the British themselves - Russian.
we are used to saying "leave in English", that is. without saying goodbye, this borrowed idiom from French (unfortunately, I don’t know how it sounds in French). As for the expression "to leave in French", this is a tracing of the English idiom "to leave French" ... means about the same the most (with a negative connotation), as the French version ... a peculiar verbal dive of residents on both sides of the English Channel ... just became less widespread in Russian due to the fact that the Russian nobility communicated mainly in French