Mimi ninakutakia mafanikio katika mtihani wa kesho.

A word-by-word breakdown is:

• Mimi = I / me
• ninakutakia = I wish you
• mafanikio = success
• katika = in
• mtihani = exam / test
• wa kesho = of tomorrow → naturally, tomorrow’s

So the structure is roughly:

• Mimi = I
• ninakutakia = I wish you
• mafanikio = success
• katika mtihani wa kesho = in tomorrow’s exam

A natural English translation is I wish you success in tomorrow’s exam.

You can leave it out.

Swahili verbs already show the subject, so nina- already tells you the subject is I. That means:

• Mimi ninakutakia mafanikio... = I wish you success...
• Ninakutakia mafanikio... = I wish you success...

Using mimi adds emphasis, contrast, or a slightly more deliberate tone. For example, it can feel like:

• As for me, I wish you success
• I personally wish you success

In everyday speech, Ninakutakia mafanikio katika mtihani wa kesho is very normal.

It can be broken into parts:

• ni- = I
• -na- = present tense / ongoing or current action
• -ku- = you
• -takia = wish for

So:

• ni-na-ku-takia
• literally: I-am-you-wishing-for

A smooth English translation is I wish you.

This is very typical Swahili verb structure:
subject + tense + object + verb root

Yes.

• kutaka = to want
• kutakia = to want for someone / to wish someone

So kutakia is basically a derived form of kutaka. In practice, you should learn kutakia as the verb used for expressing good wishes:

• Nakutakia heri = I wish you well
• Nakutakia mafanikio = I wish you success

Even though it comes from the idea of wanting, in English you normally translate it as wish, not want.

Mafanikio is the normal word used for success in Swahili.

It has the ma- prefix, and even though that prefix often looks plural to English-speaking learners, mafanikio is commonly used as a general abstract noun meaning success. So even when English uses singular success, Swahili often uses mafanikio.

In other words, don’t worry too much about translating it as singular or plural. Just learn:

• mafanikio = success

That is the standard, natural word here.

Katika means in, within, or in the context of.

Here it links success to the exam:

• mafanikio katika mtihani = success in the exam

This is a standard and fairly neutral/formal choice. Depending on the context, speakers might also use other expressions, such as kwenye, especially in casual speech. But katika is very good, correct Swahili.

So in this sentence, katika is simply the word that means in.

Wa is a linking word often translated as of. It connects mtihani and kesho:

• mtihani wa kesho
• literally: exam of tomorrow
• naturally: tomorrow’s exam

So wa is doing the job that English often does with ’s or word order.

This linking word changes depending on noun class. Here, mtihani takes wa, so:

• mtihani wa kesho = tomorrow’s exam

This is a very common Swahili pattern.

Because the wishing is happening now, even though the exam is tomorrow.

The sentence means:

• I am wishing you success now
• for the exam that will happen tomorrow

So the time word kesho belongs with mtihani:

• mtihani wa kesho = tomorrow’s exam

The verb ninakutakia stays in the present because the act of wishing is current.

Yes. A very natural shorter version is:

• Nakutakia mafanikio katika mtihani wa kesho.

That is probably what many people would say in normal conversation.

You could also hear close alternatives like:

• Nakutakia kila la heri katika mtihani wa kesho. = I wish you all the best in tomorrow’s exam.
• Nakutakia heri kwenye mtihani wa kesho. = I wish you well in tomorrow’s exam.

So the original sentence is correct, but it is not the only possible way to say it.

Swahili pronunciation is usually very regular. You can say it in syllables like this:

• Mi-mi
• ni-na-ku-ta-ki-a
• ma-fa-ni-ki-o
• ka-ti-ka
• m-ti-ha-ni
• wa
• ke-sho

A few useful notes:

• mtihani begins with m + t, so pronounce both sounds: m-ti-ha-ni
• kesho sounds roughly like keh-sho
• stress in Swahili usually falls on the second-to-last syllable

So approximately:

• MÍ-mi
• ni-na-ku-ta-KÍ-a
• ma-fa-ni-KÍ-o
• ka-TÍ-ka
• m-ti-HÁ-ni
• KÉ-sho

The stress is not usually as strong as in English, but this is a good guide.

It sounds polite, warm, and encouraging.

It is not overly dramatic, but it does sound thoughtful and supportive. Using mimi at the beginning can make it feel a little more personal or emphatic.

So the sentence works well if you want to encourage someone before an exam. It is perfectly suitable in normal conversation, writing, or a message.