Although descriptive questions have the advantage of being able to evaluate the higher mental abilities of the learners by allowing their thoughts or opinions to be directly described, the difficulties and fairness of the scoring have been pointed out as limitations. In order to solve these problems, it is necessary to examine the fundamentals of such questions rather than the issue of whether they faithfully meet the requirements of an assessment tool so as to avoid surface descriptions of the resulting limitations. For this purpose, this study analyzed learners' descriptive answers using systemic functional linguistics (SFL), which regards language as a tool of knowledge construction. The “somewhat awkward and partial learners' answer,” which is one of the categories in the scoring process, contains much information about the learner's current stage of knowledge construct development. The analysis confirmed that the learners' descriptive answers showed transitional characteristics from “everyday language” to “scientific language.” It is possible to summarize the linguistic characteristics of the learners' answers as a faded metaphor―an intermediate stage of transitioning to a complete level grammatical metaphor. From the point of view of language development, this “faded metaphor” is an important reference point for understanding “what,” “when,” and “which form” is needed for learners to attain an ideal academic language. In order to collect a variety of language data from learners, closely observe their developmental stages through the data, and introduce the results back into education, a consistent theoretical framework is needed that should be based on all these processes. The grammatical metaphor theory of systemic functional linguistics used as the theoretical basis of this paper is not only a theoretical framework that can examine the conceptualizations of subject experts(assessors) and learners(appraisees), but can also serve as a basis for collecting and analyzing language data. It also supports the concrete content of the teaching and learning methods for teaching students. Based on this, it is necessary to emphasize the role of language as an essential tool for the knowledge construction of the subject of Korean in order to provide a theoretical basis for establishing a step-by-step, systematic teaching and learning strategy, as well as contributing to the refinement of scoring training and management measures.