My account was suspended recently. I was told the reasons for the suspension in a moderator private message. However, I didn't understand them fully. Since I don't want my account to be suspended again, I would like make them clear. How can I do it? Can I ask it as a meta question?
This is not an official answer. These are just my thoughts on how you might approach this.
I will heed the call from zyx and try to assume that you are sincere in your concerns and that you are not just trying to engage in empty discussion. So, until you get a proper answer from a moderator about how you can get further details about your suspension, here are my thoughts how I would deal with your situation if I was you.
So I assume that your question simply is: After a suspension, how can one find more detailed information about the reasons for the suspension than what has been provided?
You could try to contact the moderator's privately. From what I understand you can do that here: https://math.stackexchange.com/contact. From comments to this answer it sounds like you might already have tried this.
You could also try to ask this general question on https://meta.stackoverflow.com/ since the specific answer might be helpful for others in the future..
You could also contact the StackExchange team directly since it seems like (I might be wrong here) there might be a conflict between you and the moderators. And I notice that a moderator has suggested this to you. (But then again, you might not feel that you have been wronged).
Also, if you are specifically interested in the decisions behind your suspension and if you don't feel that you are getting any answers here, you could try to contact the team behind Stackexchange.
I see here: http://stackexchange.com/about/team that they have a Community manager. Accoding to this post it looks like they have more than one and that part of their job is : "They review moderator actions, offer advice, resolve disputes.". So if you feel that you would like advice, or if you feel that there is a dispute, maybe contacting them would be an idea.
Hopefully I didn't say anything wrong in this post, and I hope that you read it remembering that I am just imagining what I would do if I had your questions.
To answer in the qusetion in the abstract:
Since I don't want my account to be suspended again, I would like make [the reasons for the suspension] clear. How can I do it?
When you receive a message from your friendly neighbourhood moderators™, respond with a request for clarification. The private messaging system is built so that a user can only reply to messages sent by the moderators (or comm team), which means that for every message we send, the user is permitted one reply.
Use that reply wisely, as the moderators are not obliged to respond to every message you send.
Can I ask it as a meta question?
It appears that you can. I am not too fond of this approach, as the moderators are severely limited in what they can disclose, and so you are unlikely to receive the best answers using this method.
I am a latecomer to the party; but, having appreciated the mathematical interest in the OP's large number of posts, I did a little digging into the past meta posts trying to find out the reason for such a prolific user being suspended.
All I can say to the community is that this issue may be kept in mind during the design of the next version of the site. Just like discussion forums have evolved into Q&A sites like this one, maybe in future there will be further evolution into even better things.
And then, some way can be incorporated to alleviate the problem of frequent bumps to the front page whenever large number of edits are done. Maybe some kind of special provision can be made for "time-consuming answer in progress," for instance by way of some flag in the database, or even an extra table for such. The post should be visible on the front page only after the user indicates that it is fully finished. But it will still be visible on the user's page, and if it is an answer, on the corresponding question page too.
This may be something inherent in math in that it can proceed at an elephant's pace taking years or decades, whereas programming needs are much quicker and so StackOverflow's designers may not have faced such issues in the past.