فجأة يعود صديقي.

فجأة means suddenly or all of a sudden. It works like an adverb here, describing how the action happens.

So the sentence structure is basically:

• فجأة = suddenly
• يعود = returns / comes back
• صديقي = my friend

Starting with فجأة gives the sentence a dramatic feel: Suddenly, my friend returns.

It is usually pronounced approximately faj’atan in careful MSA.

A few pronunciation notes:

• ف = f
• ج = usually j in MSA
• ء is a hamza, a glottal stop, like the break in uh-oh
• the final written form often appears without full vowel marks in normal text

So you can think of it as faj-ah-tan, with a small stop before the last part.

يعود is the present/imperfect form of the verb عاد, meaning to return / to come back.

So يعود means:

• he returns
• he is returning
• sometimes, depending on context, he comes back

If you wanted a clear past tense meaning, you would normally say:

• فجأة عاد صديقي = Suddenly, my friend returned

So this sentence as written is present tense, not past.

Because Arabic verbs already include the subject information.

يعود by itself already means he returns. The he is built into the verb form.

So Arabic does not need a separate pronoun here. Adding هو would usually be unnecessary unless you want emphasis:

• هو يعود = he is returning / he returns with extra emphasis

Because Arabic very often uses verb–subject order, especially in simple verbal sentences.

So:

• يعود صديقي = literally returns my friend

This is completely normal in Arabic.

You could also say:

• صديقي يعود

That is also grammatical, but it puts more focus on my friend.

Very roughly:

• يعود صديقي = neutral verbal sentence
• صديقي يعود = my friend is the one returning

The -ي means my.

• صديق = friend
• صديقي = my friend

This is a possessive suffix attached directly to the noun. Arabic often does possession this way instead of using a separate word like English my.

Because a noun with a possessive suffix is already definite.

So:

• صديق = a friend / friend
• الصديق = the friend
• صديقي = my friend

Since my friend is already specific, Arabic does not add ال.

It can cover several of those English ideas, depending on context.

عاد / يعود generally means to return. In natural English, that may be translated as:

• return
• come back
• go back

The Arabic verb itself does not always specify the same direction distinction that English does. Context tells you what sounds best in translation.

Yes. That is grammatical.

Compare:

• فجأة يعود صديقي = Suddenly, my friend returns
• صديقي يعود فجأة = My friend returns suddenly

The meaning is very close, but the focus changes a little:

• sentence-initial فجأة sounds more dramatic
• final فجأة sounds a bit more like ordinary description

Grammatically, صديقي is the subject of the verb, so it is nominative.

But because it has the possessive suffix -ي (my), the usual case ending is not clearly shown in the normal written form. In traditional grammar, the nominative ending is understood rather than pronounced separately here.

So a learner should still understand:

• functionally, صديقي is the subject
• therefore, it is nominative in grammar

Even though you do not see a normal ending like -u.

The dictionary form is عاد.

This gives you the pair:

• عاد = he returned
• يعود = he returns / he is returning

This is a very common verb in MSA, and its root is ع-و-د, which is connected with the idea of returning or coming back.