兰考的泡桐出口日本，叫兰桐，由于木质好，日本人只要兰考人生产的泡桐。
B-Thing I-Thing O B-Thing I-Thing O O B-Location I-Location O O B-Thing I-Thing O O O B-Thing I-Thing O O B-Person I-Person I-Person O O B-Person I-Person I-Person O O O B-Thing I-Thing O