American, French and Chinese

An American, a Frenchman and a Chinese went to try their echo; the American said, “Good morning,” and the echo came back, “Good morninginginging.” Then the Frenchman said, “Bon jour,” and the echo came back “Bon jourjourjour.”
Then the Chinese said, “Chang chiong shang zhang hu,” and the echo came back, “Whatwhatwhatwhat?”