Plain form + かどうかwhether or not
Used to embed a yes/no question into a larger sentence. It usually follows a plain form verb, adjective, or noun (without 'da').
Common mistakes
- Using 'da' after nouns or na-adjectives before 'ka dou ka'
- Confusing with the 'question word + ka' pattern
- Wrongly including 'dou ka' when there is already a question word like 'nani' or 'itsu'