We update the Ethical Consideration Section to specify the issues raised in the ethical meta review.

Specifically, we add a subsection "Data Collection Issues" to answer following three questions:

1. The terms and conditions of the data source;

we ensure that the collected data is **legal to use** according to the Zhihu terms(https://www.zhihu.com/term/zhihu-terms):"Information posted by users through Zhihu is public information, and other third parties can access the information posted by users through Zhihu."

2. Approval of the study;

we ensure that the research subject in this work is not human. This work does not need **ethics approval**, in the region of where it is conducted.


3. Removal of personal Information in the data.

we use two methods to ensure the data does not contain any **private information**: 1) we did not include any account information during the data collecting procedure to keep anonymous; 2) we cleaned the potential private information such as emails, id numbers, etc. to further ensure privacy.