prior/ˈpraɪə(r)/
adj.1. （常与to连用）预先的；在前的A prior engagement will preclude me from coming.我因有约在先，不能来了。
I have a prior engagement and so can't go with you.我预先有约会，所以不能跟你去。
The contract will be signed prior to the ceremony.合同将在仪式举行之前签字。
2. 更重要的；优先的This task is prior to all others.这项任务比所有其他任务都重要。
I stopped playing football because my work had a prior claim on my time.我停止了踢足球，因为我必须优先处理我的工作。