英语语法分析

The aetiology was obscure and the appropriate treatment debatable.

其病因不明，也无适当的治疗。

Further field and laboratory investigations are being performed to identify the aetiology.

正在开展进一步现场和实验室调查以查明病因。

Objective To study the aetiology and epidemiology of tick borne spotted fever in northeastern area.

目的对我国东北地区蜱传斑点热进行病原学和流行病学研究。