

У меня три сестры.
I have three sisters.
Урок начинается в три часа.
The lesson starts at three o'clock.
Ты купил три билета?
Did you buy three tickets?
"три" is in the lesson "Numbers" (Level 3), along with 19 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.