Learn Hardcore Hausa: Gobe zan aika gayyata ta waya ga abokaina. - Tomorrow I will send an invitation by phone to my friends.

zan already contains the meaning “I will” (1st person singular + future).
Because zan includes “I”, you do not need an extra ni (“I”).

So Zan aika… = “I will send…”, not just “will send”.

What exactly does zan mean, and where does it come from?

Zan is the future tense marker for “I will”.

Historically, it comes from za ni:

za = future particle (“will”)
ni = I

In fast/standard speech, za ni contracts to zan.
So:

zan aika = I will send
za ka aika → za ka aika (you masc. sg. will send)
za ta aika (she will send)
za su aika (they will send)

Only the first person singular is normally written as the single word zan.

What is the function of aika here? Is it the main verb?

Yes. Aika is the main verb and means “to send”.

In the sentence:

zan = I will
aika = send
gayyata = the invitation

So zan aika gayyata… = “I will send an invitation…”.
The other parts (ta waya, ga abokaina) describe how and to whom you are sending it.

What does gayyata mean here? Is it a verb or a noun?

In this sentence, gayyata is a noun, meaning “invitation”.

As a verb, gayyata = to invite (someone).
As a noun, gayyata = invitation.

Because it comes after aika (“send”), it is understood as the thing being sent:

aika gayyata = send an invitation.

What does ta mean in ta waya? Is it a pronoun?

Here, ta is not a pronoun; it works like a preposition of means, roughly “by / via / using”.

So:

ta waya = by phone / via phone
Compare: ta mota (by car), ta jirgi (by plane).

In this structure, ta shows the instrument or means used to do the action.

Why do we say ta waya and not just waya?

If you say only waya, it just means “phone” as a noun.

Adding ta turns it into a phrase of means:

gayyata ta waya = (an) invitation by phone / a phone invitation
It answers the question “How will you send the invitation?” → By phone.

Without ta, you would need extra words to make the “by/via” meaning clear.

What does ga mean in ga abokaina?

In this sentence, ga is a preposition meaning roughly “to / for” when talking about a recipient.

ga abokaina = to my friends

So zan aika gayyata… ga abokaina = “I will send an invitation … to my friends.”

Very often, ga is used with people as the recipients of something (letters, gifts, messages, invitations, etc.).

How is abokaina formed, and what does it literally mean?

Abokaina means “my friends” (plural).

It is built from:

aboki = friend (singular)
abokai = friends (plural)
-na = my

So abokai + na → abokaina = my friends.
The possessive -na is attached at the end to show “my”.

Can I move gobe to a different position in the sentence?

Yes. Gobe (“tomorrow”) is a time expression and can move.

Your sentence:

Gobe zan aika gayyata ta waya ga abokaina.

You can also say:

Zan aika gayyata ta waya ga abokaina gobe.

Both are correct.
Putting gobe at the beginning is very common and sounds natural, especially in spoken Hausa.

Is the word order of ta waya and ga abokaina fixed, or can I switch them?

You can normally switch those two prepositional phrases without changing the core meaning.

Your version:

…gayyata ta waya ga abokaina.

Also possible:

…gayyata ga abokaina ta waya.

Both mean that the invitation is going to your friends, by phone.
Speakers may choose one order or the other for emphasis or rhythm, but both orders are grammatically acceptable.

How would I make this sentence negative: “Tomorrow I will not send the invitation by phone to my friends”?

To negate a future sentence in Hausa, you wrap the verb phrase with ba … ba.

So:

Gobe zan aika gayyata ta waya ga abokaina.
→ Tomorrow I will send…

Negative:

Gobe ba zan aika gayyata ta waya ga abokaina ba.
→ Tomorrow I will not send the invitation by phone to my friends.

Note that:

ba comes before zan
another ba comes at the very end of the clause.