Translation guide
Expressing the idea of 'a single person' in Japanese depends on context: counting people, emphasizing 'just one', or referring to an individual. The most common way is using the counter 一人 (ひとり).
To say 'one person' when counting or stating the number of people.
The standard counter for one person. Used in almost all contexts.
Formal counter for one person, often used in official documents, reservations, or announcements.
一名様ご案内いたします。
We will seat one guest.
To stress that there is only one person, not more.
Emphasizes 'only one person' or 'just one person'. Often used in emotional or dramatic contexts.
たった一人の友達です。
He/She is my only friend.
たった一人で戦った。
I fought all alone.
Similar to たった一人, meaning 'only one person'. Slightly more literary.
ただ一人残った。
Only one person remained.
Means 'only one person' in a neutral, everyday way.
一人だけ来ました。
Only one person came.
To talk about 'a single person' as an individual, often in contrast to a group.
Means 'an individual' or 'a private person'. Used when distinguishing a person from a group or organization.
一個人としての意見です。
This is my personal opinion (as an individual).
Literally 'a solitary person'. Very formal and rarely used in conversation.
単独の人物が事件に関与した。
A single person was involved in the incident.
To express that someone does something alone, without others.
The most common way to say 'alone' or 'by oneself'. Used with verbs.
一人で映画を見た。
I watched a movie alone.
一人で旅行するのが好きです。
I like traveling alone.
Means 'alone' or 'solo', often used in formal or technical contexts (e.g., solo climbing, acting alone).
単独で登頂した。
He climbed to the summit alone.
The counter 一つ (ひとつ) is for inanimate objects. Using it for people is incorrect. Always use 一人 (ひとり) for one person.
一人の学生
one student