A challenge for prospective teachers (PTs) is to determine what students know about a topic through asking appropriate questions and being thoughtful about the wording of these questions so as to capture and reframe students’ spontaneous mathematical thinking and eventually unriddle the fuzzy boundary of students’ complex thinking. This study examined four PTs’ efforts to elicit kindergarteners’ subtraction strategies and make conclusions about their subtraction understanding. Drawing on PTs’ plans for interviewing kindergarteners on subtraction problems, interview transcripts, and reflection papers, the results suggest that PTs provided effective scaffolds, adding context to numerical problems or explaining mathematical terms and symbols as needed. However, they avoided asking problems with subtrahends greater than five, numbers above ten, and missing starts or missing subtrahends, limiting their ability to draw targeted conclusions about the students’ strengths and needs. Using effective questions allowed one PT who posed a limited variety of problems to make stronger conclusions about her student’s subtraction understanding, while asking a broader variety of problems helped another PT who used limited questions make conclusions about her student’s subtraction understanding. Based on these results, mathematics teacher educators could leverage their PTs’ strengths to either encourage multiple interviews, each targeting different problem types, or one interview with a broader variety of problem types. The results of this study further highlight the need for PTs to move beyond just asking students to explain their strategies and have them justify or represent their strategies as well.

准教师（PT）面临的挑战是，通过提出适当的问题并考虑到这些问题的措词来确定学生对某个主题的了解，从而捕捉和重构学生自发的数学思维，并最终弄清学生学习的模糊边界。复杂的思维。这项研究检查了四个PT的努力，以得出幼儿园儿童的减法策略，并对他们的减法理解做出结论。利用PT的计划，就减法问题，面试成绩单和反思文件采访幼儿园学生，结果表明PT提供了有效的支架，为数字问题增加了背景，或根据需要解释数学术语和符号。但是，他们避免了对子代数大于五，数字大于十，以及缺少开始或缺乏潜移默化的行为，限制了他们就学生的长处和需求得出有针对性的结论的能力。通过使用有效的问题，一个提出有限问题的PT可以对学生的减法理解做出更强的结论，而提出更多问题可以帮助另一位使用有限问题的PT对学生的减法理解做出结论。根据这些结果，数学老师的教育者可以利用他们的PT的优势来鼓励进行多次面试，每种面试针对不同的问题类型，或者一次面试涉及多种问题类型。这项研究的结果进一步突出了PT的必要性，而不仅仅是要求学生解释他们的策略并让他们证明或代表他们的策略。