秘密 /hi mi tsu/ or 内緒 /nai sho/ can be used.
Himitsu na surabu
Ninja is already Japanese. In English it is 'Shadow warrior', it is equivalent to assassin or secret agent.
Himitsu is secret秘密
The Kempei Tai were the Imperial Japanese Army secret police. The Tokkei Tai were the Navy secret police and the Tokko Keitsatsu were the civilian secret police.
how to say "editor" in japanese
To say old Japanese illustrations in Japanese, you say "Mukashi no Nihon no irasuto".
we say Nakagawa if we want to say inside in Japanese.
Eating healthier.
Himitsu (秘密)
Himitsu.
Himitsu (秘密)
メロン is how you say melon in Japanese.