Ninguém pode adivinhar o futuro.

Because ninguém means nobody / no one, and it is grammatically singular in Portuguese.

So you say:

• Ninguém pode... = Nobody can...

Not:

• Ninguém podem...

Even though ninguém refers to zero people, Portuguese treats it like a singular subject.

Because ninguém already carries the negative meaning.

• Ninguém pode adivinhar o futuro. = Nobody can guess the future.

In Portuguese, when a negative word like ninguém comes before the verb, you normally do not add não.

Compare:

• Ninguém sabe. = Nobody knows.
• Nada aconteceu. = Nothing happened.

But when the negative word comes after the verb, Portuguese usually does use não:

• Não vi ninguém. = I didn’t see anybody.

So in your sentence, ninguém is the subject and comes before pode, so não is not needed.

Because after poder (can / to be able to), the next verb stays in the infinitive.

So:

• pode adivinhar = can guess
• pode fazer = can do
• pode ver = can see

This is the same basic pattern as in English:

• can guess
• can do
• can see

You do not conjugate the second verb after pode.

Adivinhar usually means to guess or to divine / predict by guessing.

In this sentence, it gives the idea of guessing or knowing by some uncertain means what will happen in the future.

It is slightly different from:

• prever = to foresee / predict
• saber = to know

So:

• Ninguém pode adivinhar o futuro. = Nobody can guess the future.
• Ninguém pode prever o futuro. = Nobody can predict the future.

Both are possible, but adivinhar has more of a guessing sense.

Portuguese often uses the definite article where English may or may not use it.

Here, o futuro means the future:

• o = the
• futuro = future

So:

• adivinhar o futuro = to guess the future

Using the article is completely natural in Portuguese.
Saying just adivinhar futuro would sound incomplete or unnatural in standard Portuguese.

Here, pode means can in the sense of is able to.

• Ninguém pode adivinhar o futuro. = Nobody can guess the future.

In other contexts, pode can also mean may:

• Pode entrar. = You may come in.

So the exact meaning depends on context. In this sentence, it clearly expresses ability, not permission.

Yes, but the basic order here is the most natural and neutral one:

• Ninguém pode adivinhar o futuro.

Portuguese does allow some flexibility for emphasis, but not every rearrangement sounds equally natural.

For example:

• O futuro ninguém pode adivinhar. = The future, nobody can guess.

This is possible, but it is more emphatic or stylistically marked.

For a learner, the standard pattern is best:

• Subject + verb + infinitive + object
• Ninguém + pode + adivinhar + o futuro

Ninguém means nobody / no one.

Examples:

• Ninguém veio. = Nobody came.
• Ninguém sabe. = No one knows.

After a negative verb, it can correspond to English anybody:

• Não vi ninguém. = I didn’t see anybody.

So depending on the structure, English may translate it as nobody or anybody, but the Portuguese word is still ninguém.

In European Portuguese, ninguém is approximately pronounced like:

• neen-GAING (very roughly)

A few useful points:

• The guém part sounds nasal.
• The final -ém has a nasal sound that English does not have exactly.
• The stress is on the last syllable: nin-GUÉM

A rough full-sentence pronunciation could be:

• nin-GAING PO-deh ah-dee-vin-YAR oo foo-TOO-roo

But that is only an approximation. In European Portuguese, unstressed vowels are often reduced, so it may sound more compressed than in spelling.

Yes. Futuro is a masculine noun, so it takes:

• o futuro = the future
• um futuro = a future

That is why the article is o, not a.

You can also see this in related phrases:

• no futuro = in the future
• futuro incerto = uncertain future

Yes, and it is very natural.

• Ninguém pode adivinhar o futuro. = Nobody can guess the future.
• Ninguém consegue adivinhar o futuro. = Nobody manages to / is able to guess the future.

The difference is subtle:

• pode focuses on possibility / ability
• consegue focuses more on succeeding in doing it

In many contexts, both work well.

Yes. The verb pode is in the present tense, but the sentence expresses a general truth:

• Ninguém pode adivinhar o futuro.

It does not mean that nobody can do it only right now.
It means, more generally, that this is not something people are able to do.

This is very common in both Portuguese and English:

• Water boils at 100 degrees.
• Nobody can guess the future.

So present tense is perfectly natural here.

It can do both, just like English nobody.

Literally:

• Ninguém estava em casa. = Nobody was at home.

More generally or rhetorically:

• Ninguém pode adivinhar o futuro. = Nobody can guess the future.

Here it expresses a broad statement about human limits. It does not usually invite you to think about rare exceptions unless the context does that explicitly.

So in normal use, it simply means no one / nobody in a strong general sense.