Очередь была огромной.

to be

Breakdown of Очередь была огромной.

• очередь: the line
• огромный: huge; enormous

Questions & Answers about Очередь была огромной.

Why is огромной in the instrumental case instead of nominative? I expected огромная.

This is one of the most common questions about this sentence.

In Очередь была огромной, the adjective огромной is in the instrumental singular feminine because it is used as part of the predicate after была.

Russian often allows two patterns after быть in the past or future:

• X была огромная
• X была огромной

Both can be correct, but they are not always felt exactly the same.

Very roughly:

• nominative (огромная) can sound more like simple classification or direct description
• instrumental (огромной) is very common in predicate expressions and can sound a bit more natural or standard in many contexts

So Очередь была огромной = The line/queue was huge.

For a learner, the safest takeaway is:

• after был / была / было / были, predicate nouns and adjectives are often found in the instrumental
• but nominative is also possible in many cases, especially with adjectives

Both of these are possible:

• Очередь была огромной.
• Очередь была огромная.

The version with огромной is especially standard and natural.

What case is очередь, and why?