Um furo é comum aqui.

Um is the indefinite article, meaning a or an. In this sentence, um furo refers to a hole / a puncture / a leak / one instance of that thing, not a specific previously mentioned one.

Portuguese often uses an article where English might or might not use one, depending on the context. Here, um furo sounds like a hole is a common thing here or having a puncture is common here.

If you said just furo, that would usually sound incomplete in a normal sentence.

Yes, furo is masculine. That is why it uses um, not uma.

A useful clue is the ending -o, which is very often masculine in Portuguese, though not always. So:

• um furo
• o furo

The plural is:

• uns furos = some holes
• os furos = the holes

É is the 3rd person singular of ser in the present tense:

• eu sou
• tu és
• ele/ela/você é

It is used because the subject is singular: um furo.

So the structure is:

• Um furo = subject
• é = verb
• comum = adjective/complement
• aqui = adverb of place

Portuguese often distinguishes between ser and estar.

Here, ser is used because comum describes a general characteristic or usual situation, not a temporary state.

• é comum = is common / is usual
• está comum would sound odd in most contexts

So:

• Um furo é comum aqui. = this is generally common here

A similar pattern is:

• É normal aqui.
• É frequente aqui.

In this sentence, comum is not directly attached to the noun as an adjective before or after it. It is part of the predicate, after the verb ser.

So the sentence works like:

• Um furo = the thing being talked about
• é comum = is common

This is similar to English:

• A hole is common here

not

• a common hole here

If you say um furo comum, that means a common/ordinary hole, which is a different structure.

No. Comum has the same form for both masculine and feminine singular:

• um furo comum
• uma situação comum

In the plural, it changes to comuns:

• furos comuns
• situações comuns

So in your sentence, comum stays singular because um furo is singular.

Yes, Portuguese could also use the plural, and in many contexts that may sound more natural:

• Furos são comuns aqui.
• Os furos são comuns aqui.

The singular um furo é comum aqui can still work, especially if you mean a puncture / a hole is a common occurrence here.

Portuguese sometimes uses the singular to talk about something as a type or phenomenon, much like English can say:

• A mistake is common in this situation

So the singular is grammatically fine, but the best choice depends on context.

Aqui means here.

It refers to the place where the speaker is, or the place being talked about as here from the speaker’s point of view.

In European Portuguese, you may also hear cá, which can sometimes overlap with aqui, but aqui is the straightforward neutral word learners should know first.

Examples:

• Estou aqui. = I am here.
• Aqui é caro. = It is expensive here.

It is grammatically correct, but whether it feels natural depends a lot on context and on what furo means in that situation.

If furo means a puncture, hole, or leak, the sentence can work if you are talking generally about the area or local conditions. For example, on bad roads, having a puncture is common here.

In everyday speech, people might also choose slightly different wording, such as:

• É comum haver furos aqui.
• Os furos são comuns aqui.
• Ter um furo é comum aqui.

So yes, it is possible, but context matters.

Yes. Furo is a word with several possible meanings, depending on context. Common ones include:

• hole
• puncture
• leak
• drill hole / opening
• sometimes figurative uses such as a blunder or even a news scoop in journalism

So when you see um furo, you need the context to know which meaning is intended.

A rough guide is:

• um → sounds like oom with a nasal vowel
• furo → FOO-roo, but the final vowel is weaker in European Portuguese
• é → like eh
• comum → roughly koh-MOONG, with a nasal ending
• aqui → ah-KEE

A more EP-style rough pronunciation could be:

oom FOO-ru eh कुh-MOONG ah-KEE

A few pronunciation notes:

• European Portuguese often reduces unstressed vowels.
• Final -m in comum nasalizes the vowel.
• r in furo is the softer single r.

The most direct plural version is:

• Uns furos são comuns aqui. = some holes/punctures are common here

Or more generally:

• Furos são comuns aqui. = holes/punctures are common here
• Os furos são comuns aqui. = the holes are common here

Notice the changes:

• um → uns or no article
• furo → furos
• é → são
• comum → comuns

Yes, but that means something different.

• Um furo é comum aqui. = a hole / puncture is common here
• Há um furo aqui. = there is a hole here

So:

• é comum talks about what is usual or typical
• há talks about existence

This is an important distinction in Portuguese.