Abstract: The English past tense, one of the most important English tenses, is frequently used in both written and oral English. Therefore, it is quite significant for English learners to master the correct use of the past tense. The past tense refers to not only the past time but also the present or future time in some circumstances and it could perform many pragmatic functions. This paper aims to reveal and summarize the various functions of the past tense, such as the descriptive function, the hypothetical function, the function of expressing euphemism and politeness, etc.

Key words: past tense, pragmatic function, hypothetical function, euphemism, politeness

摘要：过去时是英语中最为常见的时态之一，被广泛用于英语书面语和口语之中。因此，掌握正确的过去时用法对英语学习者非常重要。过去时不仅可用来表示过去的时间，在某些情况下，也可用来表示现在或未来的时间,表示不同的交际意义和语用功能。该论文旨在通过相关语料的分析，揭示和总结过去时的语用功能，如它的描述功能、假设功能，表示委婉和礼貌的功能等。

关键词：过去时，语用功能，假设，委婉，礼貌