Na saya mai a kasuwa yau.

Word-by-word:

• Na – first person singular subject + perfective aspect: roughly “I (did)”.
• saya – “buy” (verb).
• mai – “oil” (here it is a noun, usually cooking oil).
• a – locative preposition: “in/at”.
• kasuwa – “market”.
• yau – “today”.

So the structure is: I + buy + oil + at + market + today.

In this sentence, na is:

• the subject marker for “I”
• in the perfective (completed) aspect

So Na saya… = “I bought / I have bought …”.

It is not “my” here. Hausa uses the same written form na for different functions:

1. Subject + perfective (as in the sentence):

   • Na saya mai. – I bought oil.

2. Possessive linker “of / belonging to”:

   • motar Malam na – the car of my teacher
   • gidan Audu – Audu’s house (here the linker is built into the noun, but same idea)

You can tell which na it is from position and structure:

• At the very beginning before a verb → usually subject marker.
• Between two nouns → usually possessive/linker.

Hausa generally marks the subject with short prefixes (or clitics) on the verb, instead of separate full pronouns in neutral sentences.

• Na saya mai. – I bought oil.
• Ka saya mai. – You (m.sg.) bought oil.
• Ya saya mai. – He bought oil.

You can add a full pronoun for emphasis or contrast:

• Ni na saya mai. – I (as opposed to someone else) bought oil.
• Ni ne na saya mai. – It’s me who bought oil.

But the normal, un-emphasised way is just Na saya… without a separate “I” word.

Na saya… is perfective aspect. In English it can map to:

• simple past:
  
  • Na saya mai a kasuwa yau. – I bought oil at the market today.
• present perfect:
  
  • Na saya mai. – I have bought oil (already).

The time adverb (yau = today, jiya = yesterday, etc.) and context decide the best English translation.

For ongoing or right-now buying, you switch to an imperfective/progressive form:

• Ina sayen mai a kasuwa. – I am buying oil at the market.
• Ina yawan sayen mai a kasuwa. – I often buy oil at the market.

saya = to buy (you are the buyer).

There is a related verb:

• sayar = to sell.

Compare:

• Na saya mai a kasuwa. – I bought oil at the market.
• Na sayar da mai a kasuwa. – I sold oil at the market.

They look similar but have opposite directions:

• saya → money goes out, you get something.
• sayar → you give something away for money.

Also note: saya is normally transitive – it usually takes an object:

• Na saya littafi. – I bought a book.
  Just Na saya without an object is only natural if the object is very clear from context (“Did you buy it?” – “Na saya.”).

In this sentence, mai is a noun meaning “oil”, typically cooking oil.

Hausa also has a very common prefix-like word mai- meaning “owner of / person who has / one characterized by”, for example:

• mai mota – car owner
• mai kudi – rich person (literally “owner of money”)
• mai kyau – beautiful / good-looking person (literally “one with beauty”).

Differences:

• Noun “oil”: usually appears by itself after verbs like in your sentence:
  
  • Na saya mai. – I bought oil.
• Owner/qualifier “mai-”: typically comes before another word:
  
  • mai gida – landlord / house owner
  • mai tafiya – traveller (one who travels).

So position and context tell you which mai it is.

a is a general locative preposition. It often corresponds to “in, at, on” depending on the noun and context. Here:

• a kasuwa ≈ “at the market / in the market”.

Some rough guidelines:

• a + place – neutral “in/at”:
  • a gida – at home
  • a makaranta – at school
  • a kasuwa – at the market
• cikin – more literally inside something:
  • a cikin gida – inside the house
  • a cikin jaka – in the bag

You can say both a kasuwa and a cikin kasuwa, but a kasuwa is shorter and very common.

Hausa does not have separate articles like “the” and “a/an”. A bare noun can be translated as either, depending on context:

• a kasuwa can be “at the market” or “at a market”.

If you really need to show that the market is specific, Hausa usually uses other tools:

• a kasuwar nan – at this market
• a kasuwar garinmu – at the market of our town
• a kasuwar da muka saba zuwa – at the market we usually go to

So there’s no direct one-word equivalent of “the”; specificity is built in with things like -r/-n endings, demonstratives, and relative clauses.

Yes. Time words like yau are quite flexible in position.

All of these are possible, with slightly different emphasis:

• Na saya mai a kasuwa yau. – neutral: I bought oil at the market today.
• Yau na saya mai a kasuwa. – emphasises “today”: Today I bought oil at the market.
• A kasuwa na saya mai yau. – emphasises the place first: At the market, I bought oil today.

The basic verb–object–place–time order in your original sentence is very natural and common. Moving yau mainly changes emphasis, not the core meaning.

Standard simple negation in Hausa wraps the sentence with ba … ba and adjusts the subject marker. For “I” in perfective:

• Ban saya mai a kasuwa yau ba.
  – I didn’t buy oil at the market today.

Structure:

• Ba + na → ban (nasalization: na → ban)
• verb and rest of the sentence
• final ba.

So the pattern is:

• Na saya mai a kasuwa yau. – I bought oil at the market today.
• Ban saya mai a kasuwa yau ba. – I didn’t buy oil at the market today.

To ask a normal yes–no question, Hausa often just uses question intonation (rising at the end) and changes the subject marker for “you”.

Examples:

• Ka sayi mai a kasuwa yau? – Did you (male, singular) buy oil at the market today?
• Kin sayi mai a kasuwa yau? – Did you (female, singular) buy oil at the market today?
• Kun sayi mai a kasuwa yau? – Did you (plural) buy oil at the market today?

You don’t need to add a word like “do/did”; the subject marker (ka/kin/kun) plus question intonation is enough.

If you want a more explicitly marked question, you can add ne/ce or a question word, but for a simple yes/no it’s not required:

• Ka sayi mai a kasuwa yau ne? – slightly more marked, still “Did you buy oil at the market today?”

Replace na with the appropriate subject marker for the perfective. Using …saya mai a kasuwa yau:

• Na saya mai a kasuwa yau. – I bought oil at the market today.
• Ka sayi mai a kasuwa yau. – You (m.sg.) bought oil at the market today.
• Kin sayi mai a kasuwa yau. – You (f.sg.) bought oil at the market today.
• Ya saya mai a kasuwa yau. – He bought oil at the market today.
• Ta saya mai a kasuwa yau. – She bought oil at the market today.
• Mun saya mai a kasuwa yau. – We bought oil at the market today.
• Kun sayi mai a kasuwa yau. – You (pl.) bought oil at the market today.
• Sun saya mai a kasuwa yau. – They bought oil at the market today.

Note: with ka/kin/kun you often see sayi instead of saya, a common alternation with some subject pronouns; both saya and sayi appear in real usage.

Yes. The sentence follows a very typical pattern:

• Subject marker – Verb – Object – Place – Time

So:

• Na (I)
• saya (bought)
• mai (oil)
• a kasuwa (at the market)
• yau (today)

This is a good default template to keep in mind:

[Subject marker] + [Verb] + [Object] + [Place] + [Time]

You can move Place or Time to the front for emphasis, but the version in your sentence is completely standard.

Use the imperfective/progressive form with ina and the verbal noun:

• Ina sayen mai a kasuwa yau.
  – I am buying oil at the market today.
  (can also mean I will be buying oil at the market today depending on context)

Structure:

• Ina – “I am / I (progressive)”
• sayen – verbal noun of saya (“buying”)
• mai – oil
• a kasuwa yau – at the market today.

So:

• Na saya mai a kasuwa yau. – completed action: I bought / I have bought oil today.
• Ina sayen mai a kasuwa yau. – ongoing or arranged action: I am (in the process of) buying oil at the market today.