This paper discusses the grammatical categories of tense-aspect expressions at a discourse level and how discourse dimensions should be connected with discourse functions. Among many tense-aspect expressions, the paper focuses on the forms ‘-ess-’ and ‘-essess-’, which are complex in a sense that they depict both tense and aspect. The results show that ‘-ess-’ has a total of five discourse functions: ‘statement of past situation,’ ‘reminiscence of past situation,’ ‘objectification of present situation,’ ‘present validation of default result’ and ‘realization of hypothetical result.’ Moreover, ‘-essess-’ represents ‘order of past situations’ and ‘present invalidation of default results.’ Also these discourse functions are related to the discourse elements of ‘topic, information, and speaker.’ The findings of this study explain the characteristics of the discourse function relevant to discourse elements. Ultimately, discourse research on tense-aspect expressions in Korean language education enables understanding of the utterance intention of Korean speakers using tense-aspect grammar. And it provides learners with the basis of using Korean correctly and appropriately.

The purpose of this study is to analyze part of speech distribution according to proficiency level in 66 Korean textbooks used in major Korean language institutes. Since the number of Korean learners with instrumental motivation has significantly increased, it becomes a very important issue to evaluate their Korean proficiency levels measured through the official assessment of Korean Proficiency Test (TOPIK). Language teaching is subject to certain target learners, and it is necessary to proceed along with studies on them by considering the utilization of their research results. With regard to the distribution of different parts of speech throughout the proficiency levels, 593,100 nouns accounted for 47.86% of the total, 267,334 verbs accounted for 21.57%, and 108,593 adjectives accounted for 8.76%. Other than these three major parts of speech, those that modify other elements of a sentence show a comparatively high percentage. Although many parts of the textbooks contain dialogues or conversational sentence examples, the percentage of abbreviated words or exclamations that represent the characteristics of the spoken language were not very high.