

Fish breathe by drawing oxygen from water through their gills.
[ˈfɪʃ ˈbrið ˈbaɪ ˈdrɔɪŋ ˈɑksɪdʒən frəm ˈwɔtər ˈθru ðɛr ˈɡɪlz.]
Check the gills: bright red means the fish is fresh.
[ˈtʃɛk ðə ˈɡɪlz: ˈbraɪt ˈrɛd ˈminz ðə ˈfɪʃ ˈɪz ˈfrɛʃ.]
The shark's gills were clearly visible as it glided past the tank.
[ðə ˈʃɑrks ˈɡɪlz wər ˈklɪrli ˈvɪzəbəl əz ɪt ˈɡlaɪdəd ˈpæst ðə ˈtæŋk.]
"gill" is in the lesson "Fishes" (Level 14), along with 10 other useful words. LinDuo has 180 topic lessons like this one, 2,375 words in total. Every word has an illustration, a transcription and pronunciation in a female and a male voice. Just 10–15 minutes a day is enough to learn them all. Free, and works offline.