É importante que você não use muito óleo para fritar o peixe.

Because Portuguese commonly uses the pattern é + adjective + que + subjunctive when giving an opinion, judgment, recommendation, or necessity about an action.

So after É importante que..., the verb in the next clause normally goes into the subjunctive:

• É importante que você use...
• É bom que ele chegue cedo.
• É necessário que nós estudemos.

This is one of the most common triggers for the subjunctive in Portuguese.

Use is the present subjunctive form of usar for você/ele/ela.

Here is the comparison:

• usar = infinitive
• você usa = present indicative
• você use = present subjunctive

Since É importante que... triggers the subjunctive, use is the correct form.

A quick comparison:

• Você usa muito óleo. = a statement/fact
• É importante que você não use muito óleo. = recommendation/necessity

Not exactly in this sentence.

On its own, Não use muito óleo! is a negative command directed at você.

But in É importante que você não use muito óleo..., it is part of a subordinate clause after É importante que, so grammatically it is subjunctive, not a standalone command.

That said, the form looks the same because the negative imperative for você uses the present subjunctive form.

In Portuguese, negation usually goes before the verb:

• não use
• não faça
• não coma

This is more straightforward than in English, where we often need do not or don’t.

So:

• você não use = you not use

That is the normal word order for negation here.

Because óleo is being treated as an uncountable/mass noun, like oil in English.

With mass nouns, Portuguese uses singular muito:

• muito óleo
• muita água
• muito sal

With countable plural nouns, you would use plural forms:

• muitos ovos
• muitas batatas

So muito óleo means a lot of oil, not many oils.

The accent in óleo shows the stressed syllable: Ó-le-o.

It is a three-syllable word, and the stress falls on the first syllable. Words stressed on the third-to-last syllable are written with an accent in Portuguese.

So the accent helps mark both pronunciation and correct spelling.

In Brazilian Portuguese, óleo is roughly pronounced like OH-lee-oh, though the exact sound is naturally more Portuguese than English.

Para + infinitive is very common for expressing purpose:

• para fritar o peixe
• para fazer o jantar
• para abrir a porta

In this sentence, para fritar o peixe means in order to fry the fish.

Because the person doing the frying is already understood to be você, Portuguese can simply use the infinitive.

You could also say:

• para você fritar o peixe
• para que você frite o peixe

But para fritar o peixe is shorter and very natural.

Sometimes yes, but in this sentence você is very helpful.

You could say:

• É importante que não use muito óleo para fritar o peixe.

However, in Brazilian Portuguese, subject pronouns are often kept more than in European Portuguese, especially when the verb form could be ambiguous.

The form use could refer to:

• eu
• você
• ele/ela
• sometimes even formal o senhor / a senhora

So keeping você makes the sentence clearer and more natural in many situations.

Portuguese uses definite articles more often than English.

So o peixe can sound very natural when referring to:

• a specific fish already understood in context
• the fish being prepared in a recipe
• the item being discussed right now

If you said just peixe, it could also be possible in some contexts, but o peixe sounds more anchored to a specific thing.

Portuguese uses ser and estar differently.

Here, é importante expresses a general evaluation: the action has importance. That calls for ser.

• É importante que você... = It is important that you...

Using estar would suggest a temporary state in a way that does not fit this structure naturally.

So with judgments like this, Portuguese normally uses ser:

• É bom que...
• É necessário que...
• É importante que...

Yes, in everyday Brazilian Portuguese, pra is extremely common in speech and informal writing.

So you will often hear:

• É importante que você não use muito óleo pra fritar o peixe.

That sounds natural and conversational.

But para is the fuller, more neutral form, and it is a safe choice for careful writing, teaching materials, and formal contexts.

It is the present subjunctive, but that does not mean simple present time in the same way as English present tense.

In sentences like this, the present subjunctive often refers to a current or future action that is being recommended, desired, doubted, or evaluated.

So use here means something like:

• when you fry the fish
• whenever you fry the fish
• in your future action of frying the fish

It is less about strict tense and more about the speaker’s attitude: recommendation/importance rather than fact.