Twelve hour clock: during the hour

What time is it?

To the Russian way of thinking, the first hour of the day is the sixty minutes from midnight up to (but not including) one a.m. Thus one can ask "Который час?" and receive an answer "Уже первый," which means its currently after midnight but before one. Since a direct equivalent in uncommon in English, one often translates it loosely, depending on the context:

Here's the complete list of typical responses.

Который час? Уже первый. What time is it? It's already between 12 and 1.
Который час? Уже второй. What time is it? It's already between 1 and 2.
Который час? Уже третий. What time is it? It's already between 2 and 3.
Который час? Уже четвёртый. What time is it? It's already between 3 and 4.
Который час? Уже пятый. What time is it? It's already between 4 and 5.
Который час? Уже шестой. What time is it? It's already between 5 and 6.
Который час? Уже седьмой. What time is it? It's already between 6 and 7.
Который час? Уже восьмой. What time is it? It's already between 7 and 8.
Который час? Уже девятый. What time is it? It's already between 8 and 9.
Который час? Уже десятый. What time is it? It's already between 9 and 10.
Который час? Уже одиннадцатый. What time is it? It's already between 10 and 11.
Который час? Уже двенадцатый. What time is it? It's already between 11 and 12.

Notice the difference in meaning between these different responses to the same question:

Который час? Два часа.What time is it? Two o'clock.
Который час? Второй.What time is it? Between one and two.