Questions & Answers about Сутки — это день и ночь.
Why does this sentence use сутки for "a full day" instead of just день?
In English, we use "day" to mean both the daytime (when it is light out) and the whole 24-hour period. Russian uses two different words. День means the daytime, while сутки specifically means a full 24-hour cycle.
Why is there a dash before это?
Russian does not use the verb "to be" (like "is" or "are") in the present tense. When you define what something is, like saying "X is Y", you write a dash followed by это. The structure literally acts like "X — this is Y".
Is сутки a plural word? It ends in -и.
Yes! Even though it translates to "a full day" (singular) in English, сутки is a plural-only noun in Russian. It works just like the English words "scissors" or "clothes" — it never has a singular form.
Since the lesson is about time words, how does сутки relate to words like вчера (yesterday)?
Time expressions like вчера (yesterday) and завтра (tomorrow) refer to the previous or next сутки (24-hour period). While день is just the daytime, a true "yesterday" includes both the день and the ночь of that 24-hour cycle.