那时中国和琉球的关系如何？
公元一三七二年，朱元璋就派杨载出使琉球。[{'character': '公', 'pinyin': 'gong1', 'highest pitch': 10.97, 'lowest pitch': 10.18, 'duration': 0.25, 'prosody hierarchy': 'null'}, {'character': '元', 'pinyin': 'van2', 'highest pitch': 10.25, 'lowest pitch': 7.26, 'duration': 0.26, 'prosody hierarchy': '#2'}, {'character': '一', 'pinyin': 'i1', 'highest pitch': 10.3, 'lowest pitch': 8.61, 'duration': 0.17, 'prosody hierarchy': 'null'}, {'character': '三', 'pinyin': 'san1', 'highest pitch': 10.84, 'lowest pitch': 9.82, 'duration': 0.21, 'prosody hierarchy': '#1'}, {'character': '七', 'pinyin': 'qi1', 'highest pitch': 11.02, 'lowest pitch': 10.22, 'duration': 0.17, 'prosody hierarchy': 'null'}, {'character': '二', 'pinyin': 'er4', 'highest pitch': 11.18, 'lowest pitch': 6.98, 'duration': 0.2, 'prosody hierarchy': 'null'}, {'character': '年', 'pinyin': 'nian2', 'highest pitch': 8.17, 'lowest pitch': 5.58, 'duration': 0.34, 'prosody hierarchy': '#3'}, {'pinyin': 'sp1', 'highest pitch': 0.0, 'lowest pitch': 0.0, 'duration': 0.24}, {'character': '朱', 'pinyin': 'zhu1', 'highest pitch': 11.55, 'lowest pitch': 10.25, 'duration': 0.17, 'prosody hierarchy': 'null'}, {'character': '元', 'pinyin': 'van2', 'highest pitch': 10.25, 'lowest pitch': 7.81, 'duration': 0.18, 'prosody hierarchy': 'null'}, {'character': '璋', 'pinyin': 'zhang1', 'highest pitch': 10.19, 'lowest pitch': 8.89, 'duration': 0.29, 'prosody hierarchy': '#2'}, {'character': '就', 'pinyin': 'jiou4', 'highest pitch': 9.98, 'lowest pitch': 7.75, 'duration': 0.24, 'prosody hierarchy': 'null'}, {'character': '派', 'pinyin': 'pai4', 'highest pitch': 9.1, 'lowest pitch': 7.15, 'duration': 0.25, 'prosody hierarchy': '#1'}, {'character': '杨', 'pinyin': 'iang2', 'highest pitch': 8.78, 'lowest pitch': 6.18, 'duration': 0.24, 'prosody hierarchy': 'null'}, {'character': '载', 'pinyin': 'zai4', 'highest pitch': 11.25, 'lowest pitch': 7.8, 'duration': 0.27, 'prosody hierarchy': '#2'}, {'character': '出', 'pinyin': 'chu1', 'highest pitch': 8.83, 'lowest pitch': 8.16, 'duration': 0.26, 'prosody hierarchy': 'null'}, {'character': '使', 'pinyin': 'shiii3', 'highest pitch': 8.16, 'lowest pitch': 6.03, 'duration': 0.16, 'prosody hierarchy': '#1'}, {'character': '琉', 'pinyin': 'liou2', 'highest pitch': 7.59, 'lowest pitch': 5.81, 'duration': 0.22, 'prosody hierarchy': 'null'}, {'character': '球', 'pinyin': 'qiou2', 'highest pitch': 7.59, 'lowest pitch': 5.67, 'duration': 0.37, 'prosody hierarchy': '#4'}]