This is an important, interesting topic. The paper is clearly written and easy to follow.

There are a number of short-comings which should be addressed in a revised version:

1.  more details on the monitoring and detection; information processing and delivery of information should be better clarified;  it is not clear what training and public information was delivered prior to and how often prior to the earthquake event;

2.  more details regarding the survey respondent recruitment, sampling, and representation should be included; is this a valid sample?

3.  the statistical analysis is very thin; need to include at a minimum standard tests of significance, prob values,  confidence interval for the comparsions between groups and categories;

4.  missed opportunities for more analysis of both differences between the characteristics of those who understood and those who did ot the EEWS; what is the role of education, social status, age, gender, previous experience, etc.

5.  more disussiion of the implications for improving earthquake warning and how to increase awareness, knowledge, comprehension and actions resulting from EEWS;

6. comparative analysis between hardware and systems between China/Sichuan and Japan/US/Mexico would be useful;

While the paper has potential, in its present form even as a brief communications, it simply raises more questions than it answers...

The paper clearly expresses the concepts described as objectives, but there are some parts to be improved/modified.

• In the title it could be better to add a reference related to the importance of the population preparedness about the EEWS, the second pillar of the paper together with the messages characteristics. It could be something like: “Effective earthquake early warning systems: appropriate messaging and population preparedness roles”.
• The description of the responders’ samples has to be better organized at the beginning of the related paragraph (starting from line 106). As example, it’s important to move in this paragraph the sentence written in the note 1, page 7 about the group B, to permit a better understanding of the survey.
• Figure 1: add the unit of measure in the legend of fig. 1(a). The caption of the figure is too long. The four regions can be described in paragraph 3, as partially done in line 73-75.
• There is a paragraph 3.2 but not a paragraph 3.1
• I agree with the other comments written by the Referee #1 (09 Mar 2021)
• My comments are strictly related to this paper, and not about the positioning of the paper in the literature about the topic “Earthquake Early Warning Systems”.
• A general revision of the language is suggested.