@stevesmi
I can understand your confusion about those two words as they may, at times, mean the same thing. I hope this can somehow clarify their difference.
Both words can mean “first” or “ahead of”.
UNA
“Una” is a position, the first one, whether independently or in relation to another or others in a group.
Una ka. = Ikaw (ay) ang una. = Ang una ay ikaw. = You are first. (Independently – the rest are ignored).
Una ka sa akin. = Ikaw (ay) ang/ay (ang) una sa akin. = You are ahead of me. (Between the two of us, you are first and it does not matter if there are still others between us. Just between the two of us, you are first).
Una ka sa lahat. = Ikaw (ay) ang/ay (ang) una sa lahat. = You are first overall/ahead of everyone or everything else.
Si Bob ay una kay Ted. = Una si Bob kay Ted. = Una kay Ted si Bob. = Bob is ahead of Ted. - The subset of Bob and Ted is exclusive, i.e., even if Bob and Ted are just a part of a bigger group and Bob is not ahead of everyone, the rest are considered irrelevant to the ranking or ordering of Bob and Ted.
Ang unang buwan ng taon ay (ang) Enero. = (Ang) Enero ang unang buwan ng taon. = The first month of the year is January/January is the first month of the year.
Ang Enero ay una sa lahat ng mga buwan. = Una ang Enero sa lahat ng mga buwan. = January is first/ahead of all the months.
Ang Marso ay una sa Hunyo. = Una ang Marso sa Hunyo. = Una sa Hunyo ang Marso. = March is ahead of June. - March as coming “first” or ahead of June is all that matters here - the other 10 months are irrelevant.
MUNA
On the other hand, “muna” is “first” but in a flowing series of things. What follows it in the series has to be mentioned or, at least, clearly understood. It is not an independent “first” because its being first is in relation to another or others. That which comes first has to be stated before you can use “muna”. Therefore, “muna” cannot be used to start a sentence.
Ikaw muna. = You first. - For this to make sense, it must be understood between the speaker and the listener as to who will follow after.
In mentioning the series, words like “b
ago” (before) and “pagkat
apos” (then after) often follows “muna”. “Bago” may loosely mean “before”, but “pagkatapos” means “following right after”. In some cases, these words are also used with “una” though.
Ikaw muna bago kami. = Bago kami, ikaw muna. = You first before us.
If we’d say “Una ka” (You are first), we may leave it at that because the information is already complete. That is what I meant by “una” being independent. However, if we’d say “Ikaw muna” (You first) out of context, it anticipates a “then who’s next?”. That is the dependence of “muna”. It is like waiting for the other shoe to drop.
Si Bob muna bago si Ted. = Bago si Ted, si Bob muna. = Bob first before Ted. - If it’s about a line of 10 people, Bob does not have to be the first in line. He may be the 3rd and Ted would usually mean the 4th.
Si Bob muna at pagkatapos, si Ted. = Bob first and then Ted (after). - sometimes we say “at pagkatapos” simply as “ ‘tapos” - “Si Bob muna ‘tapos, si Ted”. - If Bob is the 3rd in line, Ted is definitely the 4th one.
Marso muna bago Abril/Mayo, etc. = Bago Abril/Mayo, etc., Marso muna. = March comes (first) before April/May/etc.. - The use of “muna” here gives the same meaning as in the use of “una” with the months above, except that here we think of the 2 months as still part of the series. It’s like saying, “March comes ahead of June (in the series)”. With “una”, it is simply, “March comes ahead of June”.
Marso muna at pagkatapos, Abril./Marso muna ‘tapos, Abril. = March first and then April.
Imagine a contest with Peter, Paul, and Mary as the first three winners. Their rankings may be indicated by using “una” or “muna” as follows:
Una:
Una si Mary. = Si Mary ang una. = Mary is first.
Una si Peter kay Paul. = Si Peter ay una kay Paul = Una kay Paul si Peter. = Peter is ahead of Paul (Peter is first as compared to Paul).
Una si Mary kay/kina Paul at Peter. = Si Mary ay una kay/kina Paul at Peter. = Una kay/kina Paul at Peter si Mary. = Mary is ahead of Paul and Peter. (Only Mary’s rank is important. The ranking between Peter and Paul is irrelevant. Grammatically, “kina” would be correct for “kina Paul at Peter” and “kay” should be used as “kay Paul at kay Peter”. However, we sometimes omit the second “kay” when speaking.)
Muna:
Si Mary muna at pagkatapos, si Peter at si Paul. = Mary is first then Peter and Paul come after.
Si Mary muna bago si Peter at pagkatapos, si Paul. = Mary first before Peter and then Paul after.
Si Peter muna bago si Paul. = Bago si Paul, si Peter muna. = Peter comes before Paul.
Si Mary muna bago si Paul o si Peter. = Bago si Paul o si Peter, si Mary muna. = Mary comes first before Peter or Paul.
Now, to complicate matters a bit more. “Una” and “muna” may also be used together as “una muna”. It is used to put the series in correct order.
In the examples above, if the question was who placed second and third between Peter and Paul, the answer might be stated as:
Una muna si Peter bago si Paul. = Peter comes FIRST before Paul. - This means the same thing as “Si Peter muna bago si Paul”, but just adds that “first” word to the statement. So, the important word here is “muna” and “una” is just used for emphasis.
Also, usually if we use “una muna”, we place it at the start of the sentence. If placed inside the sentence, an “ang” is added before it.
Si Peter ANG una muna bago si Paul.