Akwai isassun kujeru a ɗakin.

Akwai is an existential word. It introduces the idea that something is present or exists, so it works like there is or there are in English.

In this sentence, it tells you that some chairs are present in the room.

No. Akwai can be used with both singular and plural nouns.

For example:

• Akwai kujera a ɗakin. = There is a chair in the room.
• Akwai kujeru a ɗakin. = There are chairs in the room.

English changes from is to are, but Hausa keeps akwai.

Here isassun kujeru works as a noun phrase meaning enough chairs.

In this kind of structure, isassu comes before the noun and links to it. So instead of putting enough after chairs, Hausa puts the modifier before the noun here.

The basic plural form is isassu. Before a noun, it takes a linking -n, giving isassun.

So:

• isassu = enough, sufficient
• isassun kujeru = enough chairs

That -n is a normal linking form used when this kind of modifier comes directly before the noun.

Kujeru is the plural noun chairs.

Its singular form is kujera, meaning chair.

So:

• kujera = chair
• kujeru = chairs

Ɗaki means room, while ɗakin is the definite form, meaning the room.

So:

• a ɗaki = in a room
• a ɗakin = in the room

The ending -n is part of that definite/linked form.

Here a is a locative preposition, meaning in, at, or sometimes on, depending on context.

In this sentence, it means in:

• a ɗakin = in the room

ɗ is not the same as plain d.

It is an implosive d sound, made with a slightly different movement of air. If you are a beginner, the most important thing is to notice that Hausa treats d and ɗ as different letters, so they can distinguish words.

So try to learn ɗaki with ɗ, not plain d.

You would normally use babu:

Babu isassun kujeru a ɗakin.

That means There are not enough chairs in the room or There aren’t enough chairs in the room.

So:

• akwai = there is/are
• babu = there is/are not

Yes. A cikin ɗakin means more explicitly inside the room.

So:

• a ɗakin = in the room
• a cikin ɗakin = inside the room

Both can work, but a cikin ɗakin is more specific if you want to emphasize being physically inside.