本研究利用「LARP at SCU 語料庫2022」中6 名台灣日語學習者長達三年半的縱向對話資料，從使用頻率、形式及前接動詞三個面向分析「てしまう」的習 得過程。分析結果顯示，6 名學習者中有5 名幾乎在同一時期開始使用「てしまう」，且隨著學習時間的推移，其使用頻率逐漸增加。此外，學習者在學習初期主 要使用「非意志動詞＋てしまう過去形」的形式，顯示其習得可能由此形式開始。另一方面，隨著學習的進展，有2 名學習者增加了「てしまう」非過去形的使用， 且意志動詞的使用頻率也同時提升。相對地，有3 名學習者在整個學習期間幾乎僅使用「非意志動詞＋てしまう過去形」。以上結果顯示，在形式及前接動詞的使 用上，學習者間存在顯著的個人差異。

This study analyzes the acquisition process of -te shimau using longitudinal speech data from six Taiwanese learners of Japanese, collected over three and a half years in the LARP at SCU Corpus 2022. The analysis focuses on the frequency of use, forms, and the verbs preceding -te shimau. The results revealed that five of the six learners began using -te shimau at approximately the same time, and its frequency of use increased as their learning progressed. In the early stages, the form “non-volitional verb + -te shimau (past tense)” was mainly employed, suggesting that the acquisition of -te shimau begins with this form. On the other hand, as the learning period advanced, two learners showed an increase in the use of the non-past form of -te shimau, accompanied by an increase in the use of volitional verbs. In contrast, three learners almost exclusively used the “non-volitional verb + -te shimau (past tense)” form throughout the entire period. These findings indicate significant individual differences among learners regarding both the form and the types of verbs preceding -te shimau in the acquisition process.