היא ודאי תבוא מחר.

A common pronunciation is hi va-DAI ta-VO ma-KHAR.

With vowel marks, it would be written approximately as הִיא וַדַּאי תָּבוֹא מָחָר.

A few pronunciation notes:

• היא = hi
• ודאי = vadai or va-DAI
• תבוא = tavo
• מחר = machar, where ח is a throaty sound, like ch in Scottish loch or German Bach

Each word has a clear role:

• היא = she
• ודאי = certainly / definitely / surely
• תבוא = will come
• מחר = tomorrow

So grammatically, the sentence is:

subject + adverb + verb + time expression

That is very natural Hebrew.

There is no separate word for will here, because Hebrew usually expresses the future inside the verb itself.

So תבוא already means will come.

This is different from English:

• English: she will come
• Hebrew: היא תבוא

The future meaning is built into the verb form.

תבוא is the future-tense form of לבוא (to come) for third person feminine singular: she will come.

Since the subject is היא (she), the verb must match it in gender and number.

So:

• היא תבוא = she will come
• הוא יבוא = he will come

This is one of the important things English speakers need to get used to in Hebrew: verbs often show gender.

Yes. On its own, תבוא can also mean you will come when talking to one male.

So without context, תבוא could be:

• she will come
• you (masculine singular) will come

In this sentence, היא makes it clear that the meaning is she will come.

This is one reason Hebrew sometimes keeps the subject pronoun even though it is not always required.

Here ודאי means something like certainly, definitely, or surely.

It adds confidence or certainty:

• היא תבוא מחר = She will come tomorrow
• היא ודאי תבוא מחר = She will definitely/certainly come tomorrow

In modern Hebrew, ודאי can sound a bit more formal or literary than some everyday alternatives.

Hebrew often drops subject pronouns, especially when the verb already makes the subject clear.

So ודאי תבוא מחר can also be a valid sentence if the context already tells you who is being talked about.

But in this case, היא is useful because:

• it makes the subject explicit
• it removes ambiguity from תבוא
• it can add a bit of emphasis: she will certainly come tomorrow

So it is not wrong or unnatural at all.

Because מחר is a time word that normally stands by itself, just like English tomorrow.

You say:

• מחר = tomorrow

Not:

• במחר for tomorrow in this kind of sentence

Compare:

• היא תבוא מחר = She will come tomorrow

This is similar to English, where you also do not say on tomorrow in normal speech.

No. Hebrew word order is fairly flexible, though some orders are more neutral than others.

היא ודאי תבוא מחר is a natural, neutral way to say it.

Other orders are possible, for example:

• מחר היא ודאי תבוא = Tomorrow she will certainly come
• היא תבוא מחר ודאי = possible, but less neutral and more marked
• ודאי שהיא תבוא מחר = Certainly, she will come tomorrow / It is certain that she will come tomorrow

Changing the order often changes emphasis rather than the basic meaning.

Yes, לבוא (to come) is somewhat irregular, or at least not fully straightforward, because it is a very common verb with an unusual pattern.

Its future forms are:

• אבוא = I will come
• תבוא = you (m. sg.) / she will come
• תבואי = you (f. sg.) will come
• יבוא = he will come
• נבוא = we will come
• תבואו = you (pl.) will come
• יבואו = they will come

Because it is so common, it is worth memorizing as a whole verb.

You would change the pronoun, and usually the verb too.

Examples:

• הוא ודאי יבוא מחר = He will certainly come tomorrow
• הן ודאי תבואנה מחר = They (feminine) will certainly come tomorrow — formal/literary
• הם ודאי יבואו מחר = They will certainly come tomorrow

In everyday modern Hebrew, plural feminine forms are often replaced in speech by the masculine plural form, so many speakers would simply use יבואו for mixed or even all-female groups in casual conversation.