Quero manter o trecho depois do corte.

In Portuguese, the subject pronoun is often omitted when the verb already makes the subject clear.

• quero = I want
• so (eu) quero is usually shortened to just quero

Portuguese does this much more often than English. You can say Eu quero manter o trecho depois do corte, but eu is not necessary unless you want emphasis or contrast.

Example:

• Eu quero manter o trecho, mas ele quer apagar.
  = I want to keep the section, but he wants to delete it.

Because after querer (to want), Portuguese normally uses another verb in the infinitive.

So:

• quero = I want
• manter = to keep / to maintain

Together:

• quero manter = I want to keep

This is very similar to English:

• I want to keep
• Quero manter

Other examples:

• Quero sair. = I want to leave.
• Quero ver. = I want to see.
• Quero mudar isso. = I want to change that.

Here, manter means something like:

• to keep
• to preserve
• to leave in place
• sometimes to retain

In editing or technical contexts, manter often means not removing something.

So in this sentence, it suggests:

• you do not want that section deleted
• you want it to remain after the cut

Trecho usually means a section, excerpt, passage, segment, or stretch, depending on context.

It is a very common word for a portion of something:

• a section of text
• a segment of audio/video
• a stretch of road
• a part of a larger whole

In this sentence, o trecho most naturally means the section/segment.

Examples:

• um trecho do livro = a passage from the book
• um trecho da música = a segment of the song
• um trecho da estrada = a stretch of road

Because Portuguese often uses the definite article where English may or may not use the.

• o trecho = the section / the segment

Using o makes it sound like a specific section already known from the context.

Compare:

• Quero manter trecho depois do corte → sounds unnatural/incomplete in most normal situations
• Quero manter o trecho depois do corte → natural: I want to keep the section after the cut

Because de + o contracts in Portuguese:

• de + o = do

So:

• depois de o corte → not correct in normal usage here
• depois do corte → correct

This kind of contraction is very common:

• de + a = da
• de + os = dos
• de + as = das
• em + o = no
• a + o = ao

Examples:

• depois da aula = after class
• antes do filme = before the movie

It can suggest either, depending on context, but in this sentence it most naturally describes the section located after the cut.

So the likely meaning is:

• I want to keep the section after the cut
• in other words, the portion that comes after the place where something was cut

If you wanted to make that relationship extra clear, context usually does the job. In editing contexts, this sentence is quite natural.

Yes. Após o corte is possible and means basically the same thing.

Compare:

• depois do corte = after the cut
• após o corte = after the cut

The difference is mainly in style:

• depois de is very common and everyday
• após can sound a bit more formal or written

So:

• Quero manter o trecho depois do corte. → very natural, conversational
• Quero manter o trecho após o corte. → also correct, slightly more formal

Yes. Corte is a broad word and can mean different kinds of cut, depending on context.

For example:

• a cut in video or audio editing
• a physical cut
• a reduction, as in budget cut
• a hairstyle/cut of hair in some contexts

In your sentence, the most likely meaning is an edit cut or some kind of cut point in material like text, audio, or video.

Because depois do corte is acting like a phrase that describes which section you mean.

So the structure is:

• o trecho = the section
• depois do corte = after the cut

Together:

• o trecho depois do corte = the section after the cut

This is similar to English, where descriptive phrases often come after the noun:

• the section after the cut
• o trecho depois do corte

Yes, and it would sound natural.

• trecho = section / segment / excerpt
• parte = part

Parte is a little broader and more general.
Trecho often sounds a bit more specific to a segment of text, audio, video, or a defined portion of something.

So:

• Quero manter o trecho depois do corte. → slightly more precise/technical
• Quero manter a parte depois do corte. → more general, still natural

You could say:

• Eu quero manter o trecho depois do corte.

This is grammatically correct, but usually the eu is only added if you want emphasis, contrast, or clarity.

For example:

• Eu quero manter o trecho depois do corte; você quer apagar.
  = I want to keep the section after the cut; you want to delete it.

Without special emphasis, Quero manter o trecho depois do corte is the more natural default.

In Brazilian Portuguese, trecho is pronounced roughly like:

• TREH-shoo in many accents

A few notes:

• tr stays together at the beginning
• e is like eh
• ch in Portuguese sounds like sh
• final o in Brazilian Portuguese often sounds like oo

So:

• trecho ≈ TREH-shoo

This is only an approximation using English spelling, but it can help you get close.