

Nunca provei uma ostra em toda a minha vida.
As ostras do Sado têm fama em Portugal.
O empregado abriu as ostras à nossa frente.
"a ostra" is in the lesson "Sea world" (Level 15), along with 11 other useful words. LinDuo has 180 topic lessons like this one, 2,380 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.