water 不可数名词意思是"水".two glasses of water 一杯水, drinking water 饮用水, water pollution水污染, clean/dirty water 净/脏水.
waters pl: 1.(某个国家的)领海,海域：如：We were still in British waters.我们仍在英国的领海上.
2. （某一江,湖,河,海的）水域.如：This species is found in coastal waters around the Indian Ocean. 在环印度洋沿岸的海域有这一物种.
3. 不明朗（或未知的,困难, 危险等）局面：The government has warned of stormy waters ahead.政府已告诫说,以后局势将很严重.