顾客对服务质量的不满投诉在不断增加。

There has been a rise in customer ___complaints about the poor service quality.

居民们向市政部门提交了一份关于噪音污染的投诉。

The residents submitted a ___complaint to the city council about the noise pollution.

医生记录了病人的主要症状为头痛和疲劳。

The doctor recorded the patient's main ___complaints as headache and fatigue.