Fifty-litre carboy would be the most economical size. Carboys may be retained without charge for two months.
50升的瓶子应是最经济的尺码,这些瓶子可免费保存两个月。
Was the noise a cause of the illness, or were the complaints about noise merely a symptom?
是噪音引起了(精神)病呢,还是(精神)病的症状之一是对噪音的抱怨?