| Form | Inflected form |
|---|---|
| Base | challenge |
| 3rd person singular present | challenges |
| Present participle | challenging |
| Past | challenged |
| Will future | will challenge |
| Going-to future | going to challenge |
| Imperative negative | don't challenge / do not challenge |
Sottaku
Sottaku is an app for learning Chinese, Japanese, Korean, English, Spanish, French, German, and Italian with a strong focus on SRS. It includes automatic flashcard creation for hundreds of thousands of words, grammar breakdowns in example sentences, language-specific study packs where available, adaptive quizzes, mobile apps, a browser extension, and community features. Give it a try now! All learning content is free with no limits on flashcards or study time.
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