The correct answer about the translation of "por cierto" is:
By certain
Direct translation into Spanish.
To select the correct option in Spanish, the direct translation of the phrase must be identified. In order to select the correct phrase and identify the incorrect ones, the translation of each one is shown below:
By certain: Por cierto
For sure: Sin lugar a duda
Over there: Por ahí
For now: Por ahora
As you can see, the only phrase that applies directly to the translation "por cierto" is "by certain," that's the reason why this is the correct option.
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