Empeorar vs. agravarse vs. deteriorarse
The Spanish language has a number of synonyms for the concept of a situation getting worse. 'Empeorar', 'agravarse' and 'deteriorarse' are such terms that can sometimes be used interchangeably, but often have their own nuances and contexts of use.
Empeorar
'Empeorar' is a general verb in Spanish that means to go from a better to a worse state, and it can be applied broadly across various contexts.
La calidad del aire en la ciudad puede empeorar debido a la contaminación industrial.
(The air quality in the city can worsen due to industrial pollution.)
Si no tomamos medidas, el problema económico podría empeorar.
(If we don't take action, the economic problem could get worse.)
El comportamiento de los estudiantes ha empezado a empeorar recientemente.
(The behavior of the students has started to worsen recently.)
Agravarse
'Agravarse' tends to imply that an already serious situation is becoming more severe or intense, and it is often used in medical or urgent contexts.
Los síntomas del paciente se pueden agravar si no recibe el tratamiento adecuado.
(The patient's symptoms can worsen if they don't receive proper treatment.)
La situación política se ha agravado con los recientes acontecimientos.
(The political situation has deteriorated with recent events.)
Tras el terremoto, las condiciones de vida de muchas personas se agravaron considerablemente.
(After the earthquake, the living conditions of many people considerably worsened.)
Deteriorarse
'Deteriorarse' is often used when discussing physical or material degradation and refers to the process by which something becomes impaired or declines in quality, function or condition over time.
El estado de la carretera ha comenzado a deteriorarse debido a la falta de mantenimiento.
(The condition of the road has begun to deteriorate due to lack of maintenance.)
La relación entre los dos países se deterioró tras el incidente diplomático.
(The relationship between the two countries deteriorated after the diplomatic incident.)
La salud mental de una persona puede deteriorarse si no se enfrentan sus problemas emocionales.
(A person's mental health can deteriorate if their emotional issues are not addressed.)
Summary
In summary, while all three verbs - 'empeorar', 'agravarse', and 'deteriorarse' - denote some form of worsening or decline, they do bring different shades of meaning based on context and usage: 'empeorar' has a broad application for general decline; 'agravarse' suggests an increasing severity particularly in urgent situations; and 'deteriorarse' often implies a decay or decline over time in quality or condition, particularly in physical or material things.