Continuation Task, which closely links language inputs and outputs, is considered to be an effective method in foreign language learning. This paper is an empirical research that investigates the effects of interaction and alignment of Continuation Task in Chinese as a Second Language (CSL) writing. The participants are a total of 30 Cambodian native speakers, who are arranged to one continuation group (Group A) and one control group (Group B), with every group consisting of 15 participants. Group A adopts the Continuation Task approach, and providing known texts, the participants are required to first read and then complete writing. The participants in Group B have to finish writing after listening to the known texts, without providing known texts. The results show that: (a) The Continuation Task can trigger Cambodian Chinese learners' multi-level interaction and alignment effects between continuation compositions and known texts, which are mainly manifested on vocabulary, grammar, discourse cohesion, and situation mode. (b) The Continuation Task can reduce language errors and improve the writing quality of Cambodian Chinese learners. Therefore, the Continuation Task plays a critical role in promoting learning, which further indicates its adaptability in Chinese learning.