(2:50 a.m.) Son las tres menos diez de la mañana.
Telling the time involves expressing the current hour and minutes. For the hours from 1 to 12, you can simply state the number followed by "o'clock" (e.g., three o'clock).
In terms of Minutes, one can state the number of minutes past the hour. Use the word "minutes" after the number if it's more than 1 (e.g., three twenty-five or five minutes past three).
So, based on the above, the time 2:50 a.m. can be expressed in several ways, including "it's ten to three in the morning." The expression "it's ten to three in the morning" is the most common in Spanish.
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(2:50 a.m.) Son las tres ______ diez de la mañana.