我们应该提前通知他们吗？
对此次访问，中美双方均未作事先预报。[{'character': '对', 'pinyin': 'duei4', 'highest pitch': 10.36, 'lowest pitch': 9.16, 'duration': 0.24, 'prosody hierarchy': '#2'}, {'character': '此', 'pinyin': 'cii3', 'highest pitch': 7.21, 'lowest pitch': 5.87, 'duration': 0.19, 'prosody hierarchy': 'null'}, {'character': '次', 'pinyin': 'cii4', 'highest pitch': 10.2, 'lowest pitch': 5.87, 'duration': 0.17, 'prosody hierarchy': '#1'}, {'character': '访', 'pinyin': 'fang3', 'highest pitch': 9.38, 'lowest pitch': 5.13, 'duration': 0.22, 'prosody hierarchy': 'null'}, {'character': '问', 'pinyin': 'uen4', 'highest pitch': 8.63, 'lowest pitch': 5.68, 'duration': 0.29, 'prosody hierarchy': '#3'}, {'pinyin': 'sp1', 'highest pitch': 0.0, 'lowest pitch': 0.0, 'duration': 0.13}, {'character': '中', 'pinyin': 'zhong1', 'highest pitch': 10.92, 'lowest pitch': 10.5, 'duration': 0.19, 'prosody hierarchy': 'null'}, {'character': '美', 'pinyin': 'mei3', 'highest pitch': 10.9, 'lowest pitch': 6.67, 'duration': 0.16, 'prosody hierarchy': '#1'}, {'character': '双', 'pinyin': 'shuang1', 'highest pitch': 8.61, 'lowest pitch': 6.78, 'duration': 0.23, 'prosody hierarchy': 'null'}, {'character': '方', 'pinyin': 'fang1', 'highest pitch': 8.6, 'lowest pitch': 8.19, 'duration': 0.26, 'prosody hierarchy': '#2'}, {'character': '均', 'pinyin': 'jvn1', 'highest pitch': 8.25, 'lowest pitch': 7.7, 'duration': 0.19, 'prosody hierarchy': 'null'}, {'character': '未', 'pinyin': 'uei4', 'highest pitch': 7.88, 'lowest pitch': 7.12, 'duration': 0.12, 'prosody hierarchy': 'null'}, {'character': '作', 'pinyin': 'zuo4', 'highest pitch': 7.76, 'lowest pitch': 6.45, 'duration': 0.21, 'prosody hierarchy': '#1'}, {'character': '事', 'pinyin': 'shiii4', 'highest pitch': 9.34, 'lowest pitch': 6.81, 'duration': 0.18, 'prosody hierarchy': 'null'}, {'character': '先', 'pinyin': 'xian1', 'highest pitch': 9.83, 'lowest pitch': 8.68, 'duration': 0.2, 'prosody hierarchy': '#1'}, {'character': '预', 'pinyin': 'v4', 'highest pitch': 9.93, 'lowest pitch': 6.03, 'duration': 0.2, 'prosody hierarchy': 'null'}, {'character': '报', 'pinyin': 'bao4', 'highest pitch': 6.91, 'lowest pitch': 5.28, 'duration': 0.28, 'prosody hierarchy': '#4'}]