vaihdettiin

Vaihdettiin is the passive past tense form of the Finnish verb vaihtaa, meaning to change, switch, or replace. It expresses that something was changed by someone or something, with the agent left unspecified. The form is commonly used when the doer is unknown, unimportant, or general, focusing on the occurrence of the action itself.

In Finnish, the passive past is marked with the ending -tiin. Vaihdettiin does not encode a specific subject or person; the subject is the thing that was changed. The phrase can refer to a one-time event or a completed action in the past, and it is often used in manuals, reports, news, and everyday speech to describe what happened without naming who performed the change.

Examples include:

- Auton öljyt vaihdettiin viime viikolla. (The car’s oil was changed last week.)

- Paristo vaihdettiin uuteen. (The battery was replaced with a new one.)

- Kellon ranneke vaihdettiin. (The watch band was changed.)

Vaihdettiin can also appear in contexts where multiple items are involved, by using a plural subject, for example: Paristot vaihdettiin uusiin. This keeps the same passive past meaning while indicating more than one item.

Related forms include the present passive vaihdetaan (is/are changed) and the active forms such as vaihtaa (to change) in different tense and voice. The term often appears in everyday language as well as technical or procedural writing, where the agent of the change is either obvious from context or deliberately omitted.