Alƙalin wasan ya busa sau biyu.

It is a noun phrase made of two nouns:

• alƙali = referee, judge
• wasa = game, match

When alƙali is followed by another noun, it takes a linker -n, giving alƙalin. So alƙalin wasan means something like the referee of the game or the match referee.

They look the same, but here they do different jobs:

• alƙali-n: the -n links alƙali to the following noun
• wasa-n: this -n marks wasa as definite, so wasan = the game/match

So the first -n is a connector, while the second one is part of making the second noun definite.

Ya is the 3rd-person masculine singular subject marker used with the perfective/completed action form.

So in this sentence, it tells you that the subject is:

• he
• singular
• masculine
• doing a completed action

Because alƙali is treated as masculine singular, ya is the form you expect here.

In Hausa, a finite verb normally needs a subject marker like ya, ta, sun, and so on.

So busa by itself is just the verb to blow.
Ya busa means he blew / he has blown.

That little word is an essential part of the verbal pattern, not an optional extra.

Because busa means to blow, and in a sports context it is natural to understand that the referee blew a whistle.

Hausa often leaves out an object or instrument when it is obvious from the situation. So with a referee, ya busa is normally understood as he blew the whistle.

Because sau is the word used for counting occurrences or times.

So:

• sau ɗaya = once
• sau biyu = twice
• sau uku = three times

If you said only biyu, that would usually just mean two, not twice.

Yes. It follows a very common Hausa pattern:

• Subject noun phrase: Alƙalin wasan
• Subject/TAM marker: ya
• Verb: busa
• Adverbial expression: sau biyu

So this is a very standard and useful sentence pattern to learn.

No.

• ya busa = a completed action, he blew
• yana busa = ongoing or habitual, he is blowing or he usually blows

In this sentence, the action is viewed as finished, so ya busa is the correct choice.

No. Alƙali can also mean judge in other contexts.

The basic idea is someone who decides or has authority. In a sports sentence like this one, the meaning is naturally referee.

ƙ is not the same as ordinary k in Hausa. It is a stronger, more forceful sound, often described as an ejective k.

So alƙali should not be pronounced exactly like a plain English k word. If you are a beginner, a normal k may still be understood, but it is good to notice the difference early because Hausa spelling treats k and ƙ as different consonants.