n.水下通气管；通气管
vi.用通气管潜航
With a snorkel, however, a diver can stay under water for quite a long time. 可是，潜水员携带一根通气管就可以在水下呆很长时间。
n.潜水
动词snorkel的现在分词.
n.使用水下呼吸管潜游
