Figure 6 presents the time series of all sub-topics except ‘other’. From a perspective of the general trends, the three sub-topics, ‘questioning the government and media’, ‘staying at home and taking necessary precautions’, and ‘taking scientific protective measures’ showed a similar variation tendency over time. The numbers of texts on those three sub-topics improved quickly on January 20 and peaked on the 21st, then gradually decreased but fluctuated towards January 29, rose obviously on January 31, and reached a peak on February 1. Since then, the curve has been steadily fluctuating, beginning to rise on February 5. ‘Fear and worry’, ‘objective comment’, and ‘blessing and praying’ climbed from January 20, reached their peak on 21, fell steadily, then rose again on February 5 and stabilized. ‘Appealing for aiding patients’ and ‘seeking medical help’ suddenly increased from February 6 and reached a peak around February 8. After that, the ‘appealing for aiding patients’ showed a downward trend, and the ‘seeking medical help’ remained a high concern. ‘Popularizing anti-epidemic knowledge in family’ and ‘condemning bad habits’ both started to climb on January 20. After reaching a summit on the 21st, the decline since stabilized. ‘Seeking relief materials’ began to rise on January 22, fell to a peak on 23, then stabilized after rising on February 5. ‘Willing to return work’ had a slight increase and fluctuation since January 20 and has shown a significant upward trend since February 4.