How to say meaningless in Japanese

Example Sentences

愛ai のno ないnai 人生jinsei などnado 全くmattaku 無意味muimi だda。: Life without love has no meaning.
多くooku のno 人間ningen にとってnitotte 三角関数sankakukansuu をwo 学ぶmanabu ことkoto はha 無意味muimi であるdearu ようにyouni 思えるomoeru。: I think that for many people learning the trigonometric functions is meaningless.
脅威kyoui はha 変化henka しshi 続けるtsuzukeru、進化shinka できないdekinai 防御bougyo はha 意味imi がga ないnai。: The threat increases; a defence that doesn't evolve is meaningless.
いくらikura 器ki だけdake をwo 日本一nippon'ichi にしてもnishitemo、中身nakami がga 三流sanryuu やったらyattara な～んna～n のno 意味imi もmo ないnai んn ちゃうchau のno？: The container may be the best in Japan, but if the contents are third class, then isn't it completely meaningless?
彼女のkanojono 言葉kotoba はha まったくmattaku 無意味muimi だったdatta。: What she said was completely meaningless.

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