你为什么要参加涟水保卫战？
以后，必成同志率部参加了两次涟水保卫战，策应了宿北大战的胜利。[{'character': '以', 'pinyin': 'i3', 'highest pitch': 8.24, 'lowest pitch': 7.43, 'duration': 0.13, 'prosody hierarchy': 'null'}, {'character': '后', 'pinyin': 'hou4', 'highest pitch': 9.89, 'lowest pitch': 6.76, 'duration': 0.3, 'prosody hierarchy': '#3'}, {'pinyin': 'sp1', 'highest pitch': 0.0, 'lowest pitch': 0.0, 'duration': 0.28}, {'character': '必', 'pinyin': 'bi4', 'highest pitch': 11.1, 'lowest pitch': 9.72, 'duration': 0.19, 'prosody hierarchy': 'null'}, {'character': '成', 'pinyin': 'cheng2', 'highest pitch': 8.13, 'lowest pitch': 7.04, 'duration': 0.22, 'prosody hierarchy': '#1'}, {'character': '同', 'pinyin': 'tong2', 'highest pitch': 8.13, 'lowest pitch': 6.63, 'duration': 0.22, 'prosody hierarchy': 'null'}, {'character': '志', 'pinyin': 'zhiii4', 'highest pitch': 12.19, 'lowest pitch': 6.89, 'duration': 0.28, 'prosody hierarchy': '#2'}, {'character': '率', 'pinyin': 'shuai4', 'highest pitch': 10.63, 'lowest pitch': 7.76, 'duration': 0.28, 'prosody hierarchy': 'null'}, {'character': '部', 'pinyin': 'bu4', 'highest pitch': 12.29, 'lowest pitch': 7.46, 'duration': 0.22, 'prosody hierarchy': '#2'}, {'character': '参', 'pinyin': 'can1', 'highest pitch': 8.72, 'lowest pitch': 7.08, 'duration': 0.25, 'prosody hierarchy': 'null'}, {'character': '加', 'pinyin': 'jia1', 'highest pitch': 8.47, 'lowest pitch': 7.32, 'duration': 0.17, 'prosody hierarchy': 'null'}, {'character': '了', 'pinyin': 'le5', 'highest pitch': 7.63, 'lowest pitch': 6.19, 'duration': 0.2, 'prosody hierarchy': '#1'}, {'character': '两', 'pinyin': 'liang3', 'highest pitch': 7.67, 'lowest pitch': 4.79, 'duration': 0.26, 'prosody hierarchy': 'null'}, {'character': '次', 'pinyin': 'cii4', 'highest pitch': 10.86, 'lowest pitch': 5.9, 'duration': 0.18, 'prosody hierarchy': '#1'}, {'character': '涟', 'pinyin': 'lian2', 'highest pitch': 9.68, 'lowest pitch': 7.12, 'duration': 0.19, 'prosody hierarchy': 'null'}, {'character': '水', 'pinyin': 'shuei2', 'highest pitch': 8.05, 'lowest pitch': 7.42, 'duration': 0.2, 'prosody hierarchy': '#1'}, {'character': '保', 'pinyin': 'bao3', 'highest pitch': 7.97, 'lowest pitch': 5.27, 'duration': 0.14, 'prosody hierarchy': 'null'}, {'character': '卫', 'pinyin': 'uei4', 'highest pitch': 7.16, 'lowest pitch': 5.27, 'duration': 0.17, 'prosody hierarchy': 'null'}, {'character': '战', 'pinyin': 'zhan4', 'highest pitch': 8.95, 'lowest pitch': 5.67, 'duration': 0.25, 'prosody hierarchy': '#3'}, {'pinyin': 'sp1', 'highest pitch': 0.0, 'lowest pitch': 0.0, 'duration': 0.34}, {'character': '策', 'pinyin': 'ce4', 'highest pitch': 9.82, 'lowest pitch': 8.84, 'duration': 0.24, 'prosody hierarchy': 'null'}, {'character': '应', 'pinyin': 'ing4', 'highest pitch': 8.84, 'lowest pitch': 7.62, 'duration': 0.19, 'prosody hierarchy': 'null'}, {'character': '了', 'pinyin': 'le5', 'highest pitch': 7.63, 'lowest pitch': 6.66, 'duration': 0.16, 'prosody hierarchy': '#1'}, {'character': '宿', 'pinyin': 'su4', 'highest pitch': 10.87, 'lowest pitch': 7.18, 'duration': 0.26, 'prosody hierarchy': 'null'}, {'character': '北', 'pinyin': 'bei3', 'highest pitch': 13.54, 'lowest pitch': 8.08, 'duration': 0.16, 'prosody hierarchy': '#1'}, {'character': '大', 'pinyin': 'da4', 'highest pitch': 8.1, 'lowest pitch': 7.33, 'duration': 0.21, 'prosody hierarchy': 'null'}, {'character': '战', 'pinyin': 'zhan4', 'highest pitch': 8.95, 'lowest pitch': 7.43, 'duration': 0.15, 'prosody hierarchy': 'null'}, {'character': '的', 'pinyin': 'de5', 'highest pitch': 7.44, 'lowest pitch': 6.53, 'duration': 0.09, 'prosody hierarchy': '#1'}, {'character': '胜', 'pinyin': 'sheng4', 'highest pitch': 8.95, 'lowest pitch': 7.02, 'duration': 0.21, 'prosody hierarchy': 'null'}, {'character': '利', 'pinyin': 'li4', 'highest pitch': 9.89, 'lowest pitch': 5.33, 'duration': 0.29, 'prosody hierarchy': '#4'}]