这墙上发生过什么事情？
至今墙上仍可见累累弹痕。[{'character': '至', 'pinyin': 'zhiii4', 'highest pitch': 10.36, 'lowest pitch': 9.6, 'duration': 0.21, 'prosody hierarchy': 'null'}, {'character': '今', 'pinyin': 'jin1', 'highest pitch': 10.91, 'lowest pitch': 10.17, 'duration': 0.2, 'prosody hierarchy': '#1'}, {'character': '墙', 'pinyin': 'qiang2', 'highest pitch': 10.91, 'lowest pitch': 6.24, 'duration': 0.26, 'prosody hierarchy': 'null'}, {'character': '上', 'pinyin': 'shang4', 'highest pitch': 9.18, 'lowest pitch': 6.96, 'duration': 0.23, 'prosody hierarchy': '#2'}, {'character': '仍', 'pinyin': 'reng2', 'highest pitch': 9.03, 'lowest pitch': 6.72, 'duration': 0.19, 'prosody hierarchy': '#1'}, {'character': '可', 'pinyin': 'ke3', 'highest pitch': 9.03, 'lowest pitch': 5.41, 'duration': 0.17, 'prosody hierarchy': 'null'}, {'character': '见', 'pinyin': 'jian4', 'highest pitch': 7.63, 'lowest pitch': 5.41, 'duration': 0.25, 'prosody hierarchy': '#2'}, {'character': '累', 'pinyin': 'lei2', 'highest pitch': 9.06, 'lowest pitch': 6.51, 'duration': 0.16, 'prosody hierarchy': 'null'}, {'character': '累', 'pinyin': 'lei2', 'highest pitch': 9.06, 'lowest pitch': 7.76, 'duration': 0.22, 'prosody hierarchy': '#1'}, {'character': '弹', 'pinyin': 'dan4', 'highest pitch': 9.69, 'lowest pitch': 7.02, 'duration': 0.26, 'prosody hierarchy': 'null'}, {'character': '痕', 'pinyin': 'hen2', 'highest pitch': 7.26, 'lowest pitch': 5.03, 'duration': 0.34, 'prosody hierarchy': '#4'}]