Learn Hardcore Hausa: Mutane da yawa sun zo suna gaisawa da su da safiya. - Many people came and greeted them in the morning.

You can see forms with yawa in front (or with possessive forms), like yawan mutane (“the number/amount of people”), but that tends to feel more technical, counting‑like, or formal.

For a simple descriptive “many people” in a narrative sentence, mutane da yawa is the natural, default choice.

Is sun zo just a simple past “they came”? How is it different from suka zo or suna zuwa?

Sun zo is the normal, unfocused perfective (completed) form:

sun zo – they came / they have come

Compare:

suka zo – also “they came”, but this is a focus/relative form.
You typically use suka when:
- you are focusing that part of the sentence:
  Su ne suka zo. – They are the ones who came.
- or in certain kinds of subordinate clauses (relative, etc.).
suna zuwa – “they come / they are coming”, continuous or habitual:
- suna zuwa kullum – they come every day
- suna zuwa yanzu – they are coming now

In your sentence, sun zo is a simple, narrative “they came (arrived)”.

Why do we have both sun zo and suna gaisawa together? Is that like two separate sentences?

It behaves like two closely connected clauses:

sun zo – they came (completed action)
suna gaisawa – they were greeting / they are greeting (ongoing action)

Together:

Mutane da yawa sun zo suna gaisawa da su da safiya.
Many people came, greeting them in the morning.

The combination of perfective (sun zo) + progressive (suna gaisawa) often means:

a main event (they came), and at the same time / as part of that,
a continuous activity (they were greeting).

So it is similar to English:

“Many people came and were greeting them in the morning.”
“Many people came, greeting them in the morning.”

It is one sentence with two linked verbal ideas, sharing the same subject (mutane da yawa).

What exactly is going on inside suna gaisawa?

Suna gaisawa breaks down like this:

su‑ – they (3rd person plural subject pronoun)
‑na – continuous/progressive marker
gaisawa – greeting / exchanging greetings (verbal noun from gaisa)

So suna gaisawa literally means “they are in the state of greeting / they are greeting”.

Functionally it is:

suna gaisawa – they are greeting / they were greeting (depending on context)

Even though English doesn’t repeat “they” here (“Many people came, greeting them…”), Hausa grammar normally requires the subject pronoun (su‑) before tense/aspect markers like ‑na.

What is the difference between gaisa, gaishe, gaisuwa, and gaisawa?

Learners often meet several related forms:

gaisa – to exchange greetings, usually more mutual:
- Sun gaisa. – They greeted each other / exchanged greetings.
gaishe (wani) – to greet someone (more one‑way, “greet X”):
- Na gaishe shi. – I greeted him.
gaisuwa – greeting(s), as a noun:
- Ina gaisuwa. – (lit.) I am greeting; often used like “Greetings.”
gaisawa (da wani) – exchanging greetings with someone:
- suna gaisawa da su – they are exchanging greetings with them

In your sentence, suna gaisawa da su suggests a social, back‑and‑forth greeting interaction, not just a quick one‑sided “hello”.

The word da appears three times: da yawa, da su, da safiya. Does it mean the same thing each time?

No; da is very flexible in Hausa, and its nuance changes with context.

da yawa – “many / a lot of”
- Here da helps form an adjectival idea:
  - mutane da yawa – many people
  - ruwa da yawa – a lot of water
gaisawa da su – “greeting with them”
- Here da is closer to English with:
  - Ina aiki da shi. – I work with him.
  - suna gaisawa da su. – They are greeting (exchanging greetings) with them.
da safiya – “in the morning”
- Here da introduces a time expression and is usually translated as in:
  - da safe / da yamma / da dare – in the morning / in the evening / at night
  - da safiya – in the morning

So the same word da serves different roles: “with / and / having / in (time)” depending on the phrase.

In gaisawa da su, who does su refer to? The “many people”, or some other group?

Grammatically, su is just “them” (3rd person plural independent pronoun).
Who exactly “them” are depends on context:

It could be another group that was mentioned earlier:
- e.g. “The guests arrived. Many people came, greeting them in the morning.”
  - Here su = “the guests”.
It could, in some contexts, refer back to the same people, meaning “greeting one another”:
- Mutane da yawa sun zo suna gaisawa da juna da safiya. – Many people came, greeting one another in the morning.
- With da juna we explicitly show mutual greeting.

In your exact sentence, without extra context, most listeners will assume su refers to some previously mentioned group different from the “many people” who are coming.

Why do we need da in gaisawa da su? Why not just gaisawa su?

The verb idea gaisawa da (wani) normally takes da before the person:

gaisawa da shi – exchange greetings with him
gaisawa da su – exchange greetings with them

Without da, gaisawa su would sound ungrammatical or at least very odd to a native speaker.

Compare:

gaishe shi – greet him (no da)
gaisa da shi – greet/exchange greetings with him (needs da)

So gaishe and gaisa da pattern differently.
Your sentence uses the gaisawa da pattern, which requires the da before the pronoun.

What does da safiya mean exactly? Can I also say da safe?

Da safiya literally means “with morning”, but in usage it is:

da safiya – in the morning

You will also often hear:

da safe – in the morning (very common, maybe even more common in speech)

So you can say:

Mutane da yawa sun zo suna gaisawa da su da safiya.
Mutane da yawa sun zo suna gaisawa da su da safe.

Both are acceptable; da safe is a bit more colloquial, da safiya can feel a bit more formal/explicit.

Can the time expression da safiya move to another place in the sentence?

Yes, time expressions in Hausa are quite flexible. All of these are possible:

Da safiya, mutane da yawa sun zo suna gaisawa da su.
Mutane da yawa sun zo da safiya suna gaisawa da su.
Mutane da yawa sun zo suna gaisawa da su da safiya.

Putting da safiya at the very beginning often gives it a bit more emphasis:

Da safiya, many people came and were greeting them.

All versions are understandable; preference can depend on style and rhythm.

Why does Hausa repeat su (in suna gaisawa) when we already have mutane da yawa as the subject?

In Hausa, the subject pronoun with the tense/aspect marker is part of the normal verb form and usually cannot be dropped, even if a full noun subject is present.

So:

Mutane da yawa sun zo. – Many people came.
Mutane da yawa suna gaisawa. – Many people are greeting.

You cannot normally say:

✗ Mutane da yawa na gaisawa. (without su)

In English we avoid repeating “they” after “many people”, but in Hausa:

the full noun (mutane da yawa) gives you the content (“which people”),
the subject pronoun + tense marker (su‑na, su‑n, etc.) is a grammatical requirement of the verb.

So the repetition is natural and required in Hausa, even though English wouldn’t do it.