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