A planta pode morrer sem água.

In Portuguese, singular countable nouns often appear with an article more often than they do in English. So a planta is very natural.

In this sentence, a planta can mean:

• the plant in a specific context, or
• a plant / the plant in a more general statement, depending on context.

Portuguese uses articles more broadly than English, so a planta pode morrer sem água sounds more natural than bare planta pode morrer sem água.

Planta is a feminine noun in Portuguese, so it takes the feminine singular article a.

That is why you get:

• a planta = the plant

And in the plural:

• as plantas = the plants

There is not always a logical reason for grammatical gender, so it is something you usually learn together with the noun: a planta, not just planta.

Poder is the infinitive form, meaning to be able to / can.
In the sentence, the verb has to match the subject a planta, which is third person singular, so poder becomes pode.

So:

• eu posso = I can
• você / ele / ela / a planta pode = you / he / she / the plant can

That is why the sentence uses pode.

After a conjugated modal verb like pode, the next verb normally stays in the infinitive.

So the pattern is:

• pode + infinitive
• A planta pode morrer
• literally: The plant can die

This is similar to English:

• can die not
• can dies

So morrer stays unchanged because pode is already the conjugated verb.

Sem is a preposition, and it means without.

Examples:

• sem água = without water
• sem açúcar = without sugar
• sem dinheiro = without money

It does not change form here. It simply introduces what is lacking.

In Portuguese, you often do not use an article after sem when speaking generally.

So:

• sem água = without water
• sem comida = without food
• sem ajuda = without help

You can sometimes hear an article in more specific contexts, but in a general statement like this, sem água is the normal choice.

The accent in água shows the stressed syllable and helps indicate pronunciation.

It is pronounced roughly AH-gwa, with the stress on the first syllable.

Even though água is a feminine noun, you often say:

• a água

That may look unusual because of the two a sounds together, but it is correct. The noun is still feminine:

• a água fria not
• o água frio

A natural Brazilian Portuguese pronunciation is approximately:

a PLAN-ta PO-de mo-REH sem A-gwa

A few notes:

• planta: stress on plan
• pode: stress on po
• morrer: stress on the last syllable
• água: stress on á

Depending on the region, the final r in morrer may sound softer or stronger, but the overall rhythm stays the same.

Yes, to some extent. A planta pode morrer sem água is the most neutral order.

You could also say:

• Sem água, a planta pode morrer.

This puts more emphasis on without water.

Both are correct, but the original sentence sounds very natural and straightforward.

Pode morrer expresses possibility, not certainty.

So it means:

• the plant can die
• the plant may die

If you wanted certainty, you might use something like:

• A planta vai morrer sem água. = The plant is going to die without water.
• A planta morre sem água. = The plant dies / will die without water, depending on context.

So pode morrer is less definite than vai morrer.

You would change the article, noun, and verb to plural:

• As plantas podem morrer sem água.

Changes:

• a → as
• planta → plantas
• pode → podem

The rest stays the same:

• morrer
• sem água

Not always. Planta can also have other meanings in Portuguese, depending on context, such as:

• a plant as a living thing
• a floor/story of a building
• a blueprint or floor plan

But in a sentence like A planta pode morrer sem água, the meaning is clearly a living plant. The context makes that obvious.