写论文摘要时以一般现在时为主。介绍背景知识时，要用一般现在时，例如：Speech recognition is the task of converting speech into 叙述研究现状时，也可以用一般现在时，例如：This essay is to analyse how the era influences corporate cultures， and to give suggestions on the building of corporate 叙述研究结果时，大多数用一般过去时，例如：Our text achieved the possibility
