How to ask a question with だろう in the correct way? Should I add か in the end?
I saw a lot of examples and almost always guys omit か in the end. And just say 何だろう；いつだろう。。。
Japanese Language Stack Exchange is a question and answer site for students, teachers, and linguists wanting to discuss the finer points of the Japanese language. It only takes a minute to sign up.Sign up to join this community
～だろう forms a question that is mainly addressed to yourself. It's like "I wonder". If you are clearly requesting an answer from someone else, don't use it.
Next, か after だろう in a yes/no type question corresponds to English "whether/if", and it's mandatory. か in a wh-question (i.e., a question including いつ, だれ, 何, なぜ, etc) is purely optional, but is usually omitted especially in casual speech.
- 彼は来るだろうか？ I wonder if he will come.
- これは食べられるだろうか？ I wonder if I can eat this.
- これは何だろう？ (I wonder,) What's this?
- これは何だろうか？ (I wonder,) What's this?
- どうしてだろう？ I wonder why.
- どうしてだろうか？ I wonder why.