Тренировка была полезной.

to be

Breakdown of Тренировка была полезной.

• полезный: useful
• тренировка: the training

Questions & Answers about Тренировка была полезной.

What does the verb была represent in this sentence?

Была is the feminine singular past tense form of the verb быть (to be). It links the subject тренировка with the predicate полезной, effectively translating to "was" in English.

Why is the adjective полезной in the instrumental case instead of the nominative?

In Russian, when a predicate adjective follows a past (or future) form of быть, it is typically put in the instrumental case to express the state or quality attributed to the subject. Here, полезной in the instrumental indicates that the training was in the state of being useful.

What is the grammatical gender and case of the noun тренировка, and how can you tell?

Тренировка is a feminine noun in the nominative case. The ending -а in its nominative singular form is a common indicator of feminine nouns in Russian, and the nominative case is used for the subject of the sentence.

Would it be correct to say Тренировка полезная instead of Тренировка была полезной?

While Тренировка полезная is acceptable in the present tense (since Russian often omits the verb быть in the present), it would not be appropriate for the past tense. In the past tense, the verb быть must appear (as была) and the corresponding predicate adjective must be in the instrumental case (hence, полезной).

Why is the instrumental case specifically used with adjectives after быть in past tense constructions?

The instrumental case is traditionally used with predicate adjectives following past (and future) forms of быть in Russian to denote a temporary state or quality. This grammatical structure helps to express that the subject was characterized by the quality described—here, that the training was useful.