“Opo” is the polite way to say “yes.” “Po,” on the other hand, doesn’t have any particular meaning, but using it when one speaks expresses respect to the person being addressed.
For example, when a classmate asked you:
Kumain ka na ba? (Have you eaten yet?)
The typical reply would be:
Oo, kumain na ako. (Yes, I have already eaten.)
But if a person older or someone who has a higher social status than you (like your boss) asked you the same question, the polite answer would be:
Opo, kumain na po ako. (Yes, I have already eaten)
Another example is if a co-worker around the same age asked you:
Ikaw ba ang bagong empleyado? (Are you the new employee?)
You would usually respond with:
Oo, ako nga. (Yes, I am)
But if it was your boss or an employee who is older than you the one who asked you:
Ikaw ba ang bagong empleyado? (Are you the new employee?)
The polite way to respond will be:
Opo, ako nga po. (Yes, I am)
Alternatively you can also say:
Hindi po. Matagal na po ako dito. (No, I’ve been here for a long time.)
If you’d noticed, “opo” is usually placed at the beginning of a sentence and “po” is usually placed at the end; however, this may not always be the case as “po” can also be found in the middle of a sentence and may even appear several times in the case of compound sentences.
e.g.
Patayin mo na lang ang mga ilaw pagkatapos mo. (Just turn off the lights after you’re done)
Response:
Sige po. Tatapusin ko lang po itong takdang-aralin na ginagawa ko. (Alright. I’ll just finish this homework that I’m doing.)
Another example using a compound sentence:
Nandiyan ba ang nanay mo? (Is your mother there?)
Response:
Opo. Nandito po, pero natutulog po siya. (Yes. She’s here, but she’s sleeping)
As far as I know, there are no exact rules that state where “po” should be placed, so this can be very challenging for someone who has just started learning Tagalog. The only way to get around this is to listen to how native speakers use it. It may take a lot of trial and error, but you’ll eventually get the hang of it.
Don’t worry about making a mistake because even if you ended up placing “po” in awkward places, people would usually understand and would still appreciate your attempt at being polite. A lot of people actually find it cute when non-Tagalog speakers struggle with it, although a lot more would be more impressed if you can get it right.
As always, if you have any questions, feel free to ask. (^_^)