

Это только часть круга.
This is only part of the circle.
Какая часть квадрата синяя?
Which part of the square is blue?
Отрежь мне часть пирога, пожалуйста.
Cut me a piece of the pie, please.
"часть" is in the lesson "Geometric figures" (Level 45), 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.