impelling force
impelling need
impelling factor
A: What is the main factor behind this project?
A：这个项目背后的主要推动力是什么？
B: The impelling need for innovation is the reason.
B：创新的紧迫需求就是原因。
1) 驱动的，推动的
2) 激励的，促使的
3) 迫切的
1. 促使，推动
present participle
1. Driving, forcing, or urging someone to do something
Synonym: driving, motivating, urging