Eu estudo como o Pedro quando estou motivado.

In Portuguese, subject pronouns (eu, tu, ele, etc.) are often optional, because the verb ending already shows who the subject is.

• Eu estudo como o Pedro quando estou motivado.
• Estudo como o Pedro quando estou motivado. (also correct)

Both are grammatically fine.

When do you keep eu?

• To emphasize the subject:
  
  • Eu estudo como o Pedro (but other people don’t).
• To avoid ambiguity (less common with eu, more important with other persons).
• In spoken language, some speakers simply use pronouns more often.

In your sentence, dropping eu is perfectly natural in European Portuguese.

Como can be two completely different things:

1. Verb (from comer – to eat)

   • Eu como às oito. = I eat at eight.

2. Conjunction/adverb meaning “like / as / how”

   • Eu estudo como o Pedro. = I study like Pedro (does).

In your sentence, como is not a verb. It means “like / in the same way as”.

You can tell it’s not the verb comer because:

• There is already a main verb estudo in the sentence.
• After como you have a noun phrase o Pedro, not an object of eating.

In European Portuguese, it is very common to use the definite article (o, a, os, as) before people’s names:

• o Pedro, a Ana, o João, a Maria

So:

• Eu estudo como o Pedro = I study like Pedro.

You can hear and see people say como Pedro without the article, and it’s not wrong, but:

• In Portugal, with the article is more typical and sounds more natural in everyday speech.
• In Brazilian Portuguese, people usually do not use the article with names in standard speech: they would more often say como Pedro, not como o Pedro.

Since you’re learning Portuguese from Portugal, o Pedro is the more natural choice.

In this sentence, como o Pedro expresses manner/way of doing something, not quantity.

• Eu estudo como o Pedro
  = I study the way Pedro studies / in the same manner as Pedro.

If you wanted to compare how much you study (quantity), you might say:

• Eu estudo tanto como o Pedro. = I study as much as Pedro.
• Eu estudo mais do que o Pedro. = I study more than Pedro.

So:

• como o Pedro → similarity in manner.
• tanto como o Pedro → similarity in amount.

They mean completely different things:

• como o Pedro = like Pedro / in the same way as Pedro

  • Eu estudo como o Pedro.
    I study like Pedro (does).

• com o Pedro = with Pedro

  • Eu estudo com o Pedro.
    I study with Pedro (together, side by side).

So:

• como → comparison (“like/as”).
• com → accompaniment (“with”).

Portuguese distinguishes ser and estar:

• ser = more permanent/essential characteristics
• estar = temporary states or conditions

Motivado here is a temporary state: you’re not always motivated.

• Estou motivado. = I am (currently) motivated.
• Sou motivado. would sound like “I am a motivated person (by nature/character)”, and even then it’s less natural than Sou muito motivado.

In this sentence, we’re clearly talking about moments when your motivation comes and goes, so estar is the correct choice:

• … quando estou motivado. = … when I am (feeling) motivated.

Motivado/motivada must agree with the gender of the subject:

• If the speaker is male:
  • Eu estudo como o Pedro quando estou motivado.
• If the speaker is female:
  • Eu estudo como o Pedro quando estou motivada.

In Portuguese:

• -o ending → usually masculine.
• -a ending → usually feminine.

So you must choose motivado or motivada depending on who “eu” is.

Yes, easily. Portuguese word order is quite flexible with time and condition clauses.

Your sentence:

• Eu estudo como o Pedro quando estou motivado.

Reordered:

• Quando estou motivado, eu estudo como o Pedro.

Both are correct and natural.

Notes:

• In writing, it’s common to put a comma when the quando-clause comes first.
• In speech, both orders are used; choosing one order or the other may slightly change the focus:
  • End position → stress on how you study (como o Pedro).
  • Initial position → stress on when you study (when motivated).

Portuguese present tense (Presente do Indicativo) covers both:

1. Habitual actions / general truths

   • Eu estudo como o Pedro quando estou motivado.
     = I (generally) study like Pedro when I’m motivated.

2. Actions happening now, especially in context:

   • O que estás a fazer? – Estou a estudar.
     What are you doing? – I am studying.

If you really want to emphasize right now in European Portuguese, you often use:

• estar a + infinitive:
  
  • Estou a estudar. = I am studying (right now).

In your sentence, the meaning is clearly habitual (“whenever I’m motivated”), so plain estudo is the right choice.

Yes, it’s the same written form, but the function and meaning are different:

• Como estás?
  
  • como = how (interrogative word)
• Eu estudo como o Pedro.
  
  • como = like / as (conjunction of comparison)

Portuguese uses como in several roles:

• “how” → Como se diz isto em português? = How do you say this in Portuguese?
• “like/as” → Ela fala como a mãe. = She speaks like her mother.
• “since/as” (cause, more formal) → Como não chegaste, fomos embora. = Since you didn’t arrive, we left.

In your sentence it’s clearly the “like/as” meaning.