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電話器を使って友達と話しました。
I talked to my friend using the telephone.
A device used to communicate over long distances by converting sound into electrical signals.
電話器は19世紀に発明されました。
The telephone was invented in the 19th century.
The term is somewhat outdated; modern Japanese often uses '電話' (denwa) or '携帯電話' (keitai denwa) for mobile phones.
In contemporary Japanese, '電話' (denwa) is more commonly used to refer to telephones, while '電話器' is more technical or archaic.
Composed of '電話' (telephone) and '器' (device/instrument).
While '電話器' is a valid term, it is less commonly used in modern Japanese. '電話' alone is more frequently used to refer to telephones in general.