whether or not

かどうか embeds a yes-or-no question inside a larger sentence: I do not know whether he will come. The embedded clause uses the plain form without です or ますか. It commonly precedes verbs like 分かる, 知る, 聞く, and 決める.

Examples

• 彼かれが来くるかどうか分わかりません。

  Kare ga kuru ka dou ka wakarimasen.

  I do not know whether he will come.

• パーティーに行いくかどうか、まだ決きめていません。

  Paatii ni iku ka dou ka, mada kimete imasen.

  I have not decided yet whether to go to the party.

Vocabulary in these examples

• 彼 he, him
• 来る to come
• どう how
• 分かる to understand
• パーティー party
• 行く to go

Related patterns · Quotation and embedded questions

• 〜と言う to say that (quotation)
• 〜と思う to think that
• 〜という（名前） called, named
• 疑問詞＋〜か embedded question (who, what, when ... )