A way you just thought:
A minimum level forum, only allows a currently running survey. If someone should participate in the survey, you need to apply for a survey card. You can only enter the survey only if you apply for a survey.
This avoids the user to temporarily think of the investigation, and then write a check. Afterwards, I want to modify the problem of the investigation.
Of course, a low-level forum's survey can be 2 or three.
The application for investigating cards shall be responsible for the bamboo. The user must obtain this survey card after providing the details of the spikes.
In this way, the investigation permission is only open to the bamboo. Ordinary users don't need it.
The survey can only be dealt with only medium and senior users bamboo.
In the investigation, once someone started voting, it is not allowed to be modified. Alternatively, once a survey has 10 people vote, it is not allowed to be investigated, avoiding the incorrect voting results.
