Translation guide
The English suffix '-er' forms agent nouns (person or thing that does something) and comparative adjectives. This guide covers how to express these concepts in Japanese.
Express a person who performs an action or has a role, like 'teacher' or 'runner'.
For nouns that describe an activity, use をする人 to mean 'person who does N'.
サッカーをする人は元気です。
People who play soccer are energetic.
者 (もの) is a formal or literary suffix meaning 'person'. It attaches to verbs or nouns, often in set phrases.
若者は新しい技術に詳しい。
Young people are familiar with new technology.
家 (か) is a suffix meaning 'specialist' or 'professional', like 'artist' or 'novelist'. It attaches to nouns.
彼は小説家です。
He is a novelist.
Express a tool, device, or thing that performs an action, like 'opener' or 'dryer'.
Attach もの (thing) to the stem of a verb to mean 'thing that does V'. This is a general and productive pattern.
これは缶を開けるものです。
This is a can opener.
機 (き) means 'machine' and is used for mechanical devices, like 'washing machine' or 'dryer'.
洗濯機が壊れました。
The washing machine broke.
器 (き) means 'device' or 'instrument', often for smaller tools or appliances.
加湿器をつけてください。
Please turn on the humidifier.
Express a higher degree of a quality, like 'bigger' or 'faster'.
Use のほうが to mark the subject and より to mark the comparison target. The adjective remains in its base form.
この車はあの車より速いです。
This car is faster than that car.
A simpler comparative structure without のほうが. Still natural and common.
今日は昨日より暑い。
Today is hotter than yesterday.
Use もっと before an adjective to mean 'more ...' without an explicit comparison target.
もっと大きいサイズはありますか？
Do you have a bigger size?
There is no single Japanese suffix that directly corresponds to '-er'. Instead, use the patterns above depending on whether you mean a person, thing, or comparison. Translating word-for-word often results in unnatural Japanese.
人 (ひと) is the most general and conversational. 者 (もの) is formal and often used in set compounds. 家 (か) is for professionals or specialists. Choose based on context and register.