Результаты эксперимента записаны в отчёте.

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Breakdown of Результаты эксперимента записаны в отчёте.

• результат: the result
• отчёт: the report
• эксперимент: the experiment

Questions & Answers about Результаты эксперимента записаны в отчёте.

What grammatical cases are used in Результаты эксперимента, and why?

In Результаты эксперимента you have two nouns:

• Результаты is in the nominative plural (it’s the subject of the sentence).
• Эксперимента is in the genitive singular, acting as an attributive genitive (“of the experiment”). The genitive case here shows possession or relation (“results of the experiment”).

Why is эксперимента singular rather than plural?

Because the sentence refers to one specific experiment. If you meant several experiments, you would say результаты экспериментов (genitive plural).

What part of speech is записаны, and how does it function here?

Записаны is a short-form passive past participle (краткое страдательное причастие прошедшего времени) derived from записать. It serves as the main predicate in a passive construction, describing the state/result (“are recorded”). It agrees in number (plural) with the subject результаты.

Why isn’t the auxiliary verb были used (as in были записаны)?

In Russian, when you use a short-form passive participle in the past or present, the copular verb быть is often omitted. Saying Результаты эксперимента были записаны is grammatically correct and more explicit, but the simpler Результаты эксперимента записаны is perfectly natural and common in formal or scientific contexts.