

Я постоянно спотыкаюсь об этот порог.
I constantly trip over this threshold.
Бабушка стала часто спотыкаться на лестнице.
Grandma has started to stumble on the stairs a lot.
Почему ты всё время спотыкаешься на ровном месте?
Why do you keep tripping on flat ground?
"спотыкаться" is in the lesson "Accident" (Level 24), along with 9 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.