emergency的形容词是emergent
emergent:adj.新兴的;处于发展初期的;
emergency:n.突发事件;紧急情况;
复数: emergencies
The government has declared a state of emergency following the earthquake.
地震发生后政府已宣布进入紧急状态。
Interactions among different levels lead to emergent properties.
自然属性源自不同尺度单元间的相互影响。