Sy is by die projek betrokke.

Here, Sy means she.

Why:

• It is the subject of the sentence.
• It comes directly before the verb is.

This is a common point of confusion because sy can also mean his in other contexts.

For example:

• Sy is hier. = She is here.
• Dit is sy boek. = That is his book.

So in this sentence, the structure makes it clear that Sy = she.

Because is in Afrikaans also means is.

A useful thing for learners: Afrikaans verbs are much simpler than English verbs. The verb wees (to be) does not change in the present tense the way English does.

You get:

• Ek is = I am
• Jy is = you are
• Hy is = he is
• Sy is = she is
• Ons is = we are
• Hulle is = they are

So is is used for all persons in the present tense.

Because Afrikaans uses by idiomatically with betrokke.

In English, we say:

• involved in a project

In Afrikaans, the usual combination is:

• betrokke by a project
  or, in the word order used here,
• by die projek betrokke

So you should not translate the preposition word-for-word. With betrokke, Afrikaans normally uses by, even when English uses in.

The version you were given is a very natural Afrikaans pattern.

With betrokke, Afrikaans often places the prepositional part before betrokke:

• Hy is by die saak betrokke.
• Sy is by die projek betrokke.

You may also come across:

• Sy is betrokke by die projek.

That is understandable and also used, but by die projek betrokke is especially idiomatic in Afrikaans.

So the main thing to learn is this pattern:

• is by + noun + betrokke

Here betrokke is functioning like an adjective, meaning involved.

It comes after is, so it is a predicate adjective:

• Sy is betrokke. = She is involved.

Although it is historically related to a past participle, learners can safely treat it as an adjective in sentences like this.

Also, Afrikaans does not change it for gender or number here:

• Hy is betrokke.
• Sy is betrokke.
• Hulle is betrokke.

The form stays betrokke.

No. Betrokke can have a few related meanings depending on context.

Common meanings include:

• involved
• concerned
• relevant
• the person/thing in question

Examples:

• Sy is by die projek betrokke. = She is involved in the project.
• die betrokke persoon = the person concerned / the relevant person
• die betrokke dokumente = the relevant documents

So in your sentence, the presence of by die projek tells you that betrokke means involved.

Yes. Die is the Afrikaans definite article, so here it means the.

A few useful points:

• die is used for all genders
• die is also used for plural nouns
• Afrikaans does not have separate forms like English the, or German der/die/das

So:

• die projek = the project
• die boeke = the books

If it were indefinite, you would use:

• ’n projek = a project

Afrikaans spelling is usually more phonetic than English spelling.

So:

• English project
• Afrikaans projek

A few things are happening:

• the j in Afrikaans sounds like English y
• the final k represents the hard k sound clearly
• spelling is generally kept closer to pronunciation

So projek is pronounced roughly like pro-YEK.

A rough English-friendly pronunciation is:

say is bay dee pro-YEK bə-TRO-kə

A few notes:

• Sy sounds roughly like say
• by sounds roughly like bay
• die is usually like dee
• projek has stress on the second syllable: pro-YEK
• betrokke is roughly bə-TRO-kə

This is only an approximation, but it is a good starting point for an English speaker.