Comprobamos la velocidad de centrifugado y el detergente líquido.

Because comprobamos has the same form in two tenses:

• present indicative: we check / we verify
• preterite: we checked / we verified

This is normal for many -ar verbs in the nosotros form. Spanish usually relies on context to make the time clear.

For example:

• Cada vez que lavamos, comprobamos la velocidad... = Every time we wash, we check the speed...
• Ayer comprobamos la velocidad... = Yesterday we checked the speed...

So by itself, comprobamos is ambiguous.

Spanish often leaves out subject pronouns because the verb ending already shows who is doing the action.

• comprobamos already tells you the subject is we
• so nosotros comprobamos... is possible, but usually unnecessary

You would include nosotros only for emphasis, contrast, or clarity.

For example:

• Comprobamos la velocidad... = neutral
• Nosotros comprobamos la velocidad... = We check the speed (maybe not someone else)

Comprobar means to check, to verify, or to make sure.

In Spain, comprobar is very common in instructions, manuals, and more formal speech. In everyday English, check is often the best translation.

So here it means something like:

• we check
• we verify
• we make sure about

It is slightly more formal or precise than some other verbs like mirar (to look at).

Spanish uses articles more often than English.

Here, la velocidad and el detergente sound natural because Spanish often includes the definite article when referring to:

• specific items being checked
• categories already understood from context
• things in instructions or procedures

So Spanish prefers:

• la velocidad de centrifugado
• el detergente líquido

where English might leave the article out in a checklist-style phrase.

Literally, it means speed of spinning or spin speed.

In the context of washing machines:

• velocidad = speed
• centrifugado = spinning / spin cycle

So velocidad de centrifugado is the speed used during the spin cycle.

This is a very natural expression in appliance-related Spanish.

Because centrifugado functions here as a noun-like word meaning spinning or spin cycle.

So:

• centrifugar = to spin / to centrifuge (verb)
• centrifugado = spinning / spin cycle (noun or noun-like form in this context)

Spanish commonly uses noun + de + noun structures like this:

• velocidad de centrifugado
• programa de lavado
• tiempo de secado

Using de centrifugar would sound unnatural here.

Because in Spanish, adjectives usually come after the noun.

So the normal order is:

• detergente líquido = liquid detergent

If you said líquido detergente, it would sound unusual, marked, or unnatural in ordinary Spanish.

The basic pattern is:

• noun + adjective
• detergente + líquido

Yes. Adjectives in Spanish agree with the noun in gender and number.

Here:

• detergente is singular
• it is used with el, so it is masculine here
• therefore the adjective is líquido (masculine singular)

Compare:

• el detergente líquido
• los detergentes líquidos

If the noun were feminine plural, the adjective would change accordingly.

Yes. They are both direct objects of the verb.

The structure is:

• Comprobamos = verb
• la velocidad de centrifugado = first direct object
• y = and
• el detergente líquido = second direct object

So the sentence means that the action of checking applies to both things.

Yes, especially in a practical context such as:

• a manual
• instructions
• a checklist
• customer service or technical advice

It sounds clear and standard in Spain.

One small nuance: by itself, comprobar el detergente líquido can sound slightly broad, as if you are checking the liquid detergent in general. In a very specific context, Spanish might sometimes say something more precise, such as:

• comprobamos la cantidad de detergente líquido
• comprobamos el nivel de detergente líquido

But the original sentence is still perfectly understandable and natural.

Because they follow different stress rules.

• líquido has stress on the first syllable: LÍ-qui-do
• without the accent mark, Spanish speakers would stress it differently
• so the accent is needed

But comprobamos follows normal stress rules:

• words ending in -s are normally stressed on the second-to-last syllable
• so comproBAmos needs no written accent

So:

• líquido = accent needed
• comprobamos = no accent needed