遊泳

1. Origins, structure, and basic meaning

• Structure: 遊泳 is a noun and irregular intransitive verb read ゆうえい, meaning swimming, whether by a person or by an animal moving through water.
• Basic usage: Use 遊泳が禁止される for swimming being prohibited and 水槽の中を遊泳する for fish swimming through a tank.
  • この浜では波が高い日の遊泳が禁止されています。 says that swimming is prohibited at this beach on days when the waves are high; 水槽の中をゆったり遊泳する魚を眺めました。 describes watching fish swim leisurely through the tank.

2. Common pitfalls and similar expressions

• 遊泳が禁止される
  • In the passive form, が marks swimming as the activity being prohibited.
• 波が高い日の
  • の limits the swimming ban to days with high waves.
• 水槽の中を遊泳する
  • を marks the space through which the fish swim.