Ill-conditioned structure problem, also known as ill-conditioned definition problem, refers to a problem with multiple solutions, multiple solutions and a few deterministic conditions. These conditions are not only difficult to operate, but also contain some uncertain factors, such as what concepts, rules and principles are needed for the solution method? How to organize them? Which scheme is the most suitable and so on. The problem of poor structure is a common problem in daily practice, which generally exists or arises in a specific situation. The solution of ill-structured problems may need to integrate knowledge from different contents and fields, and there are many solutions, so it is difficult to have the same answer. For example, solving pollution problems may involve knowledge of mathematics, science, physics and psychology. The problem of poor structure is closely related to daily life practice, which is interesting and has great challenge significance and performance space for learners.

The main characteristics of the ill-conditioned structural problem are: (1) the components of the problem are unknown or unknown to some extent, the controllable parameters/variables are few, and the target definition is vague or lacking; (2) There are many solutions, methods and standards for evaluating solutions, and even no solutions; (3) Due to different situations, there are no prototype cases for reference; (4) Not sure which concepts, rules and principles are necessary to form a solution, and organize them; (5) There are no applicable general rules or principles, and there is no clear method to determine appropriate actions; (6) Learners need to express their personal views or beliefs about problems, so the process of solving problems is a unique process of interpersonal interaction; (7) Learners need to judge the problem and explain the reasons.