非完整体（imperfective aspect）是一种语法体。它提及从特定观点可被看作正在进行的、惯常的、重复的或一般包含内部结构的行动。对立用法是完整体，它把行动看作一个单一整体。
英语实例.在陈述句中，非完整体通常用来描述背景状况（“It was midnight. The room was dark. The rain was beating down. Water streamed in through a broken window. A gun lay on the