誠(まこと)truth, reality, sincerity, honesty, integrity, fidelity, that's right (used when recalling forgotten information, suddenly changing the subject, etc.)

その話(はなし)は嘘(うそ)か誠(まこと)か。

Is that story a lie or truth? {truth, reality, sincerity, honesty, integrity, fidelity, that's right (used when recalling forgotten information, suddenly changing the subject, etc.)}

誠(まこと)を尽(つ)くしてくれた両親(りょうしん)に感謝(かんしゃ)をする。

I express gratitude to my parents who devoted their sincerity to me. {truth, reality, sincerity, honesty, integrity, fidelity, that's right (used when recalling forgotten information, suddenly changing the subject, etc.)}

将軍(しょうぐん)：「嘘(うそ)をついてはならぬ。誠(まこと)の話(はな)をせよ。」

Shogun: 'You must not lie. Tell the truth.' {truth, reality, sincerity, honesty, integrity, fidelity, that's right (used when recalling forgotten information, suddenly changing the subject, etc.)}

誠(まこと)の武士(ぶし)なら、主人(しゅじん)のために命(いのち)を惜(お)しまずに戦(たたか)って当然(とうぜん)だ。

If one is a true samurai, it is only natural to fight without sparing one's life for one's master. {truth, reality, sincerity, honesty, integrity, fidelity, that's right (used when recalling forgotten information, suddenly changing the subject, etc.)}

生徒(せいと)に誠(まこと)の情(じょう)を尽(つ)くしたものですから、そんな生徒(せいと)とのお別(わか)れは寂(さび)しいです。

Since I devoted my sincere feelings to the students, saying goodbye to such students is sad. {truth, reality, sincerity, honesty, integrity, fidelity, that's right (used when recalling forgotten information, suddenly changing the subject, etc.)}