Sy reageer vandag.

In this sentence, sy means she.

Afrikaans uses sy both as:

• the subject pronoun: she
• the possessive determiner: her

So:

• Sy reageer vandag. = She is responding today.
• Dit is sy boek. = It is her book.

The meaning depends on the sentence structure.

Reageer means to react or to respond, depending on context.

In Sy reageer vandag, it most naturally means:

• She is responding today or
• She reacts today

In everyday English, responding is often the smoothest translation if someone is replying to something. But reacting can also be correct if the context is about an emotional or physical reaction.

Afrikaans verbs do not change according to the subject the way English verbs sometimes do.

Compare:

• English: I respond, she responds
• Afrikaans: ek reageer, sy reageer

The verb stays the same regardless of who is doing the action:

• Ek reageer
• Jy reageer
• Hy reageer
• Sy reageer
• Ons reageer

This is one of the simpler parts of Afrikaans grammar.

Yes. Sy reageer vandag is in the present tense.

Afrikaans often uses the simple present where English might use either:

• She responds today or
• She is responding today

Which English translation sounds best depends on context. Afrikaans does not always make that same distinction as explicitly as English does.

Vandag means today.

In this sentence, it comes after the verb:

• Sy reageer vandag.

That is a very normal word order in Afrikaans.

You can also move vandag to the front for emphasis:

• Vandag reageer sy.

When a time word like vandag comes first, the verb usually stays in the second position, and the subject follows it.

Afrikaans main clauses usually follow a verb-second pattern. In a normal statement with the subject first, the order is:

• Subject + verb + rest

So:

• Sy reageer vandag

Not:

• Sy vandag reageer

Putting vandag between the subject and verb would sound wrong in a standard main clause.

Yes, absolutely.

Both are correct:

• Sy reageer vandag.
• Vandag reageer sy.

The difference is mainly emphasis:

• Sy reageer vandag. = neutral statement
• Vandag reageer sy. = emphasis on today

This fronting of vandag is very common in Afrikaans.

A helpful approximate pronunciation is:

• ree-ah-KHEER

A few notes:

• The g in Afrikaans is usually a guttural sound, not a hard English g
• The stress is usually on the last part: -geer
• The first part rea- is pronounced separately, not like one English syllable

If you pronounce it carefully as ree-a-geer, you will be understood.

Yes, it is fairly common, especially in contexts like:

• replying to a message
• reacting emotionally
• responding to news
• reacting to medicine or treatment
• responding to a situation

Depending on context, Afrikaans speakers might also use other verbs, such as:

• antwoord = answer
• reply = reply
• reageer = react/respond

So reageer is natural, but the exact best choice depends on what kind of response is meant.

The infinitive is also reageer.

Afrikaans dictionaries usually list the verb in this form:

• reageer = to react / to respond

Unlike English, there is no separate to attached directly to the infinitive form itself. If needed, Afrikaans uses om te before the verb in some constructions:

• Sy wil reageer. = She wants to respond.
• Dit is belangrik om te reageer. = It is important to respond.

Yes. Grammatically, it can mean either, depending on context.

Afrikaans present tense often covers meanings that English splits into:

• simple present: she reacts
• present progressive: she is reacting / she is responding

So without more context, Sy reageer vandag could be interpreted in more than one way. In real usage, the situation usually makes the intended meaning clear.