Mwanachama huyo alisoma ilani mara mbili kabla ya kuamua chama atakachokiunga mkono.

In Swahili, demonstratives usually come after the noun, not before it.

So:

• mwanachama huyo = that member
• literally: member that

Also, huyo agrees with mwanachama, which is a human noun in noun class 1.

A rough comparison:

• huyu = this person / this one
• huyo = that person / that one
• yule = that one over there

So mwanachama huyo means that member or the member in question.

Alisoma breaks down like this:

• a- = he/she
• -li- = past tense
• -soma = read / study

So alisoma means he/she read.

A useful point for English speakers: Swahili often puts the subject and tense inside the verb itself, so you do not need a separate word for he or she.

It can mean either, depending on context.

The verb kusoma can mean:

• to read
• to study

In this sentence, because the object is ilani (manifesto), the natural meaning is read:

• alisoma ilani = he/she read the manifesto

Ilani often means manifesto, declaration, or public statement.

In a political context, especially with chama (party), ilani usually means a party manifesto.

So here it is most naturally understood as the manifesto.

Mara mbili means twice.

Literally:

• mara = time / occasion
• mbili = two

So:

• mara mbili = two times
• natural English: twice

This is a very common Swahili way to express repetition:

• mara moja = once
• mara mbili = twice
• mara tatu = three times

Kabla ya means before, and it is commonly followed by a noun or an infinitive/verbal noun.

So:

• kabla ya kuamua = before deciding

Here, kuamua is the infinitive to decide, but after kabla ya it works much like deciding in English.

So the structure is very natural:

• kabla ya + infinitive
• before + -ing

Yes, you could, and it would also be natural.

Compare:

• kabla ya kuamua = before deciding
• kabla hajaamua = before he/she decided or before he/she has decided

The version in your sentence is a little more neutral and compact. It focuses on the action deciding itself, rather than explicitly repeating the subject.

Swahili often keeps the noun explicit where English might use which one or leave it understood.

So:

• kuamua chama atakachokiunga mkono
• literally: to decide the party that he/she will support

In natural English, we usually say:

• to decide which party he/she would support

So the Swahili structure is a bit more explicit, but it is completely normal.

Chama belongs to noun class 7. Its plural is vyama (class 8).

This matters because words that refer back to chama must agree with its noun class. That is why you see class-7 forms in the relative clause:

• -cho- = relative marker for class 7
• -ki- = object marker for class 7

Both refer back to chama.

So the grammar is showing agreement with party.

A helpful breakdown is:

• a- = he/she
• -ta- = future
• -ka-cho- = future relative part meaning something like that ... will
• -ki- = it (class 7 object marker, referring to chama)
• -unga = the verb stem from kuunga mkono

So atakachokiunga mkono means:

• that he/she will support it
• with it referring to the party

Put more naturally in English:

• the party that he/she will support

For many learners, the key idea is simply that this whole chunk is a relative clause attached to chama.

Because they are doing two different jobs.

• -cho- links the verb to chama as the noun being described:
  the party that ...
• -ki- is the object marker inside the verb, meaning it, again referring to chama

So:

• chama atakachokiunga mkono
• the party that he/she will support

Even though both refer to chama, one is a relative marker and the other is an object marker.

The basic expression is:

• kuunga mkono = to support

Literally, it comes from the idea of joining/adding a hand, but in modern use it simply means to support.

When an object marker is added, it goes into the verb before the stem:

• ku-unga mkono = to support
• ki-unga mkono = support it

So in the sentence:

• atakachokiunga mkono
• that he/she will support it

The word mkono stays separate because it is part of the fixed expression kuunga mkono.

This is a tense-matching difference between the two languages.

Swahili says:

• atakachokiunga mkono
• literally: that he/she will support

But in English, after a past-tense main verb like read, we often shift the later future into would:

• The member read the manifesto twice before deciding which party he/she would support.

So the Swahili future is perfectly normal. English just tends to backshift the tense in this kind of sentence.

No. Swahili does not mark gender here.

In alisoma and atakachokiunga, the subject marker a- can mean:

• he
• she

So the sentence could refer to either a man or a woman unless the wider context makes it clear.