Cada observação da professora me ajuda a fazer um resumo mais claro.

Because the subject is cada observação.

In Portuguese, cada is grammatically singular, so the noun and the verb that go with it stay singular:

• Cada observação ajuda...
• Cada aluno chegou cedo.

Even though cada refers to multiple individual items in a general sense, Portuguese treats it as one at a time, so the verb is singular.

Cada means each.

So:

• Cada observação da professora... = Each comment/observation from the teacher...
• Todas as observações da professora... = All the teacher’s comments/observations...

The difference is in perspective:

• cada looks at the items individually
• todas as looks at them as a group

In this sentence, cada suggests that every individual remark helps.

Da is the contraction of:

• de + a = da

Here, de shows a relationship like of / from:

• a observação da professora = the teacher’s observation/comment
• literally: the observation of the teacher

This is a very common way to express possession or association in Portuguese.

Compare:

• o livro do aluno = the student’s book
• a ideia da professora = the teacher’s idea

Not necessarily in the literal English sense.

In Portuguese, observação can mean:

• an observation
• a remark
• a comment
• feedback
• a note

In a school or academic context, observação da professora often sounds more like:

• the teacher’s comment
• the teacher’s feedback
• the teacher’s remark

So even if the English meaning has already been given, it is useful to know that observação often has a broader meaning than English observation.

Me is the object pronoun meaning me.

So:

• me ajuda = helps me

In Brazilian Portuguese, object pronouns often come before the verb in everyday speech and writing:

• Ela me ajuda. = She helps me.
• A professora me chama. = The teacher calls me.

You may also learn forms like ajuda-me, but in Brazilian Portuguese that sounds more formal, literary, or European Portuguese-like. For normal Brazilian usage, me ajuda is the standard choice.

In me ajuda a fazer, the a links ajudar to another verb in the infinitive.

So the structure is:

• ajudar alguém a fazer algo
• to help someone do something

Examples:

• Ela me ajuda a estudar. = She helps me study.
• Isso ajuda a entender o texto. = That helps (someone) understand the text.

So a fazer means to do / to make after help.

You may hear that in informal speech, but the more standard and widely taught form is:

• me ajuda a fazer

After ajudar, both patterns can appear in real life, but ajudar a + infinitive is the safest and most standard option for learners.

So if you are writing or speaking carefully, use:

• ajuda a fazer
• ajuda a entender
• ajuda a melhorar

Um resumo means a summary, while o resumo means the summary.

Here, um resumo sounds natural if the idea is general: the teacher’s comments help the speaker produce a clearer summary.

Use o resumo if both speaker and listener already know exactly which summary is meant:

• A professora me ajuda a fazer o resumo. = The teacher helps me make the summary / the specific summary

Use um resumo when the focus is more on the type or result, not a specific known item.

Because claro describes resumo, and resumo is a masculine singular noun.

Agreement in Portuguese means adjectives usually match the noun they describe in gender and number:

• um resumo claro = masculine singular
• uma explicação clara = feminine singular
• resumos claros = masculine plural
• explicações claras = feminine plural

So:

• um resumo mais claro is correct
• mais clara would only be correct with a feminine noun, such as uma explicação mais clara

In Portuguese, adjectives often come after the noun, especially when they describe it in a straightforward way.

So:

• um resumo claro
• uma aula interessante
• um texto difícil

This is the normal order in Portuguese.

Sometimes adjectives can come before the noun, but that often changes the tone, emphasis, or style. For learners, the safest pattern is:

• noun + adjective

So um resumo mais claro is the expected order.

Literally, more clear. In natural English, that is usually clearer.

With writing or speaking, claro often means:

• clear
• easy to understand
• well explained

So um resumo mais claro means a summary that is easier to understand or better organized in expression.

Yes. A few possible variations are:

• Cada observação da professora ajuda-me a fazer um resumo mais claro.
• As observações da professora me ajudam a fazer um resumo mais claro.
• Cada comentário da professora me ajuda a fazer um resumo mais claro.

The differences are:

• ajuda-me is more formal or less typical in everyday Brazilian Portuguese
• As observações... me ajudam changes the subject to plural
• comentário is a different word, closer to comment

The original sentence sounds natural and standard in Brazilian Portuguese.

Yes, resumo is a very common word. It usually means:

• summary
• brief overview
• short written account of the main points

In school contexts, fazer um resumo often means:

• to write a summary of a text
• to condense the main ideas
• to make a short version of something studied

So this sentence sounds very natural in an academic setting.