Random words test pure finger speed; real sentences test actual typing. Sentence mode serves complete sentences — capitals at the start, commas and periods in the middle — which means your Shift key, your punctuation reach, and your reading-ahead all get exercised. It's noticeably harder than word mode, and noticeably closer to the typing you do all day.
That's what makes it the best practice format for real-world speed. Emails, essays, code comments, chat messages — none of them are random word salad. Training on sentences builds the exact coordination (capital → word → comma → space, without breaking rhythm) that word-mode tests never touch.
Clicking through sets sentence mode in the app — no account needed, as always. Your sentence-mode scores are tracked separately from word mode, so both trends stay honest, and the full stats, leaderboard, and challenge links all work here too.