هي تؤكد الموعد الآن.

هي is not strictly necessary.

The verb تؤكد already tells you the subject is either she or you masculine singular, depending on context. So Arabic often drops the separate subject pronoun.

• هي تؤكد الموعد الآن = She is confirming the appointment now
• تؤكد الموعد الآن = also possible, but less explicit

Using هي can do two things:

• make the subject clearer
• add a little emphasis to she

So this sentence is perfectly natural, but the pronoun is there for clarity or emphasis, not because Arabic always requires it.

Yes. By itself, تؤكد can mean either:

• she confirms / is confirming
• you confirm / are confirming when speaking to one male

That is because in the present tense, third person feminine singular and second person masculine singular often have the same verb form.

So:

• هي تؤكد clearly means she confirms
• أنتَ تؤكد means you confirm to one male

The pronoun هي removes the ambiguity.

It is pronounced approximately tu-ʾak-ki-du.

More carefully in MSA: tuʾakkidu.

A few helpful points:

• the ت gives tu-
• the ؤ represents a hamza sound, a small catch in the throat
• the middle consonant is doubled in pronunciation, even though the shadda is not written in ordinary unvoweled text

So the full word, when fully vowelled, is تُؤَكِّدُ.

Because of Arabic spelling rules for hamza.

In تؤكد, the hamza is written as ؤ, which is a hamza seated on و. This is an orthographic rule, not because there is a real w sound there.

So تؤكد is not pronounced like there is a separate w in the middle. It is still tuʾakkidu, with a hamza sound.

For a learner, the main thing to remember is:

• ؤ here = a hamza spelling
• not a long oo
• not an extra w

It can mean either, depending on context.

The Arabic present tense often covers both:

• simple present: she confirms
• present progressive: she is confirming

Because the sentence has الآن meaning now, the progressive reading is more likely in most contexts:

• هي تؤكد الموعد الآن = She is confirming the appointment now

So الآن helps push the meaning toward something happening at this moment.

الموعد is the direct object of the verb تؤكد.

The structure is:

• هي = subject
• تؤكد = verb
• الموعد = the thing being confirmed
• الآن = time expression, now

So الموعد is the thing receiving the action of confirming.

Also, the الـ on الموعد means the, so it is the appointment or the موعد, not just an appointment.

It would be accusative, because it is the direct object.

So in fully vowelled MSA, you would expect:

• هي تؤكد الموعدَ الآن

with فتحة on the end of الموعد.

In normal Arabic writing, short vowels and case endings are usually omitted, so you normally just see:

• هي تؤكد الموعد الآن

Yes, this word order is normal, and الآن can move.

This sentence has a very natural order:

• هي تؤكد الموعد الآن

But Arabic word order is flexible, so you may also see:

• هي الآن تؤكد الموعد
• تؤكد هي الموعد الآن in more marked or formal contexts
• تؤكد الموعد الآن if the pronoun is dropped

Putting الآن at the end is very common and natural. Moving it earlier can shift the emphasis slightly, but the meaning stays basically the same.

Because Arabic does not use a separate present-tense to be in this kind of sentence.

In English, you need:

• she is confirming

In Arabic, the present-tense verb itself carries the meaning:

• تؤكد

So Arabic does not need an extra word for is here. The single verb already means confirms / is confirming depending on context.