أفكر في الزواج.

A fully vocalized version is أُفَكِّرُ فِي الزَّوَاجِ.

A helpful pronunciation guide is ufakkiru fī z-zawāji.

A few things to notice:

• أفكر is pronounced ufakkiru, with a doubled k sound because of the hidden shadda on ك.
• الزواج is written with ال but ز is a sun letter, so the l sound of ال is not pronounced. So الزواج sounds like az-zawāj in isolation.
• After في, in connected speech, it often sounds like fiz-zawāj.

أفكر is a first-person singular imperfect verb, so it means I think, I am thinking, or I am considering, depending on context.

It comes from the verb فكّر meaning to think about or to consider.

So:

• أفكر = I think / I am thinking
• The أ at the beginning marks I in the imperfect tense

In Arabic, the verb itself already shows the subject.

So أفكر already means I think / I am thinking.
You do not need أنا unless you want emphasis or contrast.

For example:

• أفكر في الزواج = I’m thinking about marriage
• أنا أفكر في الزواج = I’m the one thinking about marriage / adds emphasis

Yes, في often means in, but after certain verbs it has a wider meaning.

With فكّر, the expression فكّر في means to think about or to consider.

So this is not a word-for-word in marriage translation in English. It is a normal Arabic pattern:

• فكّر في شيء = to think about something

That is why أفكر في الزواج means I am thinking about marriage / getting married.

Arabic often uses a noun where English might prefer a verb phrase.

Here, الزواج means marriage, and the whole phrase أفكر في الزواج naturally means I’m thinking about marriage or I’m thinking about getting married.

So Arabic is using the noun marriage, but in English the most natural translation may use getting married.

In Arabic, abstract nouns and general concepts are often expressed with الـ.

So الزواج here refers to marriage as an idea or institution, not necessarily one specific wedding.

This is very natural in Arabic.
Without الـ, زواج would sound more like a marriage or some marriage, which is not what is usually meant here.

So:

• الزواج = marriage in a general sense
• زواج = a marriage / some marriage

Because ز is one of the sun letters.

When الـ comes before a sun letter, the l sound is assimilated into the next consonant.

So:

• Written: الزواج
• Pronounced: az-zawāj (or in connected speech after في, roughly fiz-zawāj)

This is a pronunciation rule only. The spelling stays the same.

Because it comes after the preposition في.

In Standard Arabic, a noun after a preposition is usually genitive, so it takes kasra:

• في الزواجِ

So the final -i sound is there because في requires the genitive case.

In normal Arabic writing, short vowels are usually not written, so you normally just see:

• في الزواج

Not usually.

In this sentence, أفكر في... means I am thinking about... or I am considering..., not I believe... or in my opinion...

So:

• أفكر في الزواج = I am thinking about marriage
• أظن أن... or أعتقد أن... would be closer to I think that... in the sense of opinion

This is an important distinction for English speakers, because English uses I think in more than one way.

Yes.

The Arabic imperfect can cover several present-time meanings, depending on context:

• I think about marriage
• I am thinking about marriage
• I am considering getting married

In real usage, أفكر في الزواج often suggests I’m considering marriage / getting married, especially if someone says it about themselves. Context tells you which meaning is most natural.