口罩; 呼吸面具，防毒面具
1. 防毒面具：breathing bag 氧气囊 | breathing mask 防毒面具 | breccia 角砾岩
2. 呼吸面具：breathing machine 呼吸机 | breathing mask 呼吸面具 | breathing tube 呼吸管
3. 口罩：織物透氣性 breathe | 口罩 breathing mask | 雙面繡花針法 bred-stitch
4. 呼吸面具 防毒面具：breathing hole || 通气孔 | breathing mask || 呼吸面具 防毒面具 | breathing of engine || 发动机(曲轴箱)通风
1. breathing mask
1. Pupils learn how to use a mask, flippers and breathing regulator in a pool as well as in the ocean.