Meaning of かどうか in Japanese

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Definition of かどうか

かどうか(kadouka)

かどうかん(kadoukan) 【仮道管】

Before meeting your guests also be sure to carefully check that the toilet door locks.

"Pretty gem, isn't it?" Not knowing if it was a suitable subject or not, but anyway I tried to get her interest that way.

あの人ひとに彼女かのじょがいるかどうか知ってる？

Do you know if he has a girlfriend?

Do you know if Lucy can speak Japanese?

You have only to ask him if he'd like to join us.

It has not yet been decided whether to approve of your proposal.

あなたの質問しつもんに正直に答えるこたえるかどうかは、彼かれの主義しゅぎの問題もんだいだ。

It is a matter of principle with him to answer your questions honestly.

あなたがそれを好むこのむかどうかは問題もんだいではない。

Whether you like it or not doesn't matter.

あなたがこられるくるかどうか連絡れんらくしてする下さいください。

Let us know whether you can come.

"This must be living in the city," thought the Little House, and didn't know whether she liked it or not.