自發性語言中常見各種講話不流暢的現象，如使用填補詞、重複述說、話語中斷、代換詞語等。不流暢係因講者的語言系統需要更多時間規劃產出，或規劃過程出現困難。即便如此，不流暢不見得會影響聽者理解句子，有時反而有所助益，因為不流暢會在語流中產生停頓，引起聽者的注意，讓他們能更清楚地辨識詞彙，利用情境與上下文來理解句子。雖然不流暢對語言理解的作用似乎是中性的，但過多的不流暢現象會增加句子裡依存語和中心語之間的依存距離，干擾聽者單詞整合到心智表徵結構的過程，觸發工作記憶的時間衰退。要降低來源語不流暢的影響，同步口譯員可以採取切塊技巧，並以訊息的連貫性而非完整性為主要目標。

Disfluencies, such as fillers, repetitions, truncation, and substitution, are a common occurrence in spontaneous speech. They appear when the speech production system requires more time to plan, or the planning process was poor. However, disfluencies do not necessarily impact sentence comprehension, and in some cases can even enhance it. They provide a brief pause in the speech stream and draw the listener's attention, facilitating word recognition and enabling the use of contextual information for better understanding. Despite the seemingly neutral effect on language comprehension, excessive disfluency increases the dependency distance between the dependent word and its controlling word in a sentence. This distance interferes with the process of word integration into the mental representation and invokes time-decay of working memory in the listener. To mitigate the impact of disfluency in the source speech, the simultaneous interpreter could adopt chunking techniques and prioritize message coherence over completeness.