Put your Korean into practice.

Learn useful Korean grammar, build vocabulary and use what you learn in your own writing and text conversations. OneLine brings lessons, examples and AI feedback together to help you express what you mean.

LEARN A PATTERN, THEN USE IT
Explore Korean grammar lessons with explanations and examples. Practise using patterns with sentence transformations, then try them in your own writing.

WRITE ABOUT YOUR LIFE
Start with a daily prompt and find useful words, patterns and example answers before you write. Express your own thoughts in Korean. AI coaching suggests more natural phrasing and explains grammar in English.

PRACTISE REAL BACK-AND-FORTH
Reply in Korean in a text conversation with Buddy, your AI coach. Get help as you chat, then review feedback from your conversation.

BUILD VOCABULARY YOU CAN USE
Save useful words and grammar patterns to revisit. Practise with fill-in-the-blank exercises and writing activities. Listen to Korean lesson examples as you learn.

KEEP YOUR PRACTICE GOING
See your completed writing and conversation practice on your calendar. Return to saved writing, words and patterns whenever you want to review.

START FREE
Explore lessons, examples, vocabulary and free practice activities. Writing, saving and your streak stay free. New accounts include 7 AI corrections for freeform writing and one introductory text conversation.

ONELINE PRO
Continue with AI corrections and text conversations, listen to your corrected writing, and get AI feedback on your own word and grammar practice. Pro is available as a monthly or annual subscription. Prices and any eligible offers are shown in the app.

Subscriptions renew automatically unless cancelled through Google Play settings.

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