Dobbiamo smaltire l'olio esausto e conferire la batteria esausta.

Dobbiamo means we must, we have to, or we need to.

It is the 1st person plural form of dovere (to have to / must) in the present tense:

• io devo = I must
• tu devi = you must
• lui/lei deve = he/she must
• noi dobbiamo = we must
• voi dovete = you must
• loro devono = they must

So dobbiamo + infinitive works like we have to + verb in English.

Because after dobbiamo, Italian normally uses the infinitive of the next verb.

So:

• dobbiamo smaltire = we have to dispose of
• dobbiamo conferire = we have to take/deliver for disposal

This is the same pattern as English:

• we must dispose
• we have to deliver

You do not conjugate the second verb here.

This is because of the definite article.

• olio is a masculine singular noun, so its article is normally il
• but before a vowel, il becomes l'

So:

• il libro
• l'olio

Meanwhile, batteria is feminine singular, so it takes la:

• la batteria

That gives:

• l'olio
• la batteria

The apostrophe shows elision: the article loses its final vowel before a word beginning with a vowel.

So:

• il olio → l'olio

This is very common in Italian:

• l'acqua
• l'amico
• l'idea
• l'olio

It helps the phrase flow more naturally in speech.

Because adjectives in Italian usually agree in gender and number with the noun they describe.

• olio is masculine singular → esausto
• batteria is feminine singular → esausta

So:

• l'olio esausto
• la batteria esausta

This agreement is a basic feature of Italian grammar.

Here it means something like spent, used-up, or waste.

In this context:

• olio esausto = used oil / waste oil
• batteria esausta = dead battery / spent battery

Be careful: esausto can also mean exhausted when talking about a person.

For example:

• Sono esausto = I am exhausted

So the exact meaning depends on context.

In Italian, adjectives often come after the noun, especially when they are giving a straightforward, descriptive quality.

So:

• olio esausto
• batteria esausta

This is more normal in Italian than putting the adjective first.

English often puts adjectives before the noun, but Italian frequently prefers the opposite order.

They are related, but they are not exactly the same.

• smaltire = to dispose of, to get rid of properly, to process as waste
• conferire = to take/deliver something to the proper collection point or facility

So in waste-disposal language:

• smaltire l'olio esausto suggests properly disposing of the used oil
• conferire la batteria esausta suggests taking the dead battery to an authorized place for collection

Conferire is especially common in official, municipal, or recycling language.

It is common in formal, administrative, and recycling contexts, but it can sound a bit technical in everyday conversation.

You might see it in:

• recycling instructions
• municipal notices
• waste-disposal guidelines

In casual speech, people may prefer more everyday phrases such as:

• portare la batteria in discarica
• portare la batteria all'isola ecologica
• buttare la batteria negli appositi contenitori
  (depending on context)

So yes, it is a real and useful verb, but it often feels more official.

Italian uses articles more often than English does.

So even where English might say:

• used oil
• dead battery

Italian often prefers:

• l'olio esausto
• la batteria esausta

This is very normal. In many contexts, leaving out the article would sound unnatural or would change the meaning.

Sometimes Italian can avoid repeating an adjective, but in this sentence repeating it is clearer and more natural.

So:

• Dobbiamo smaltire l'olio esausto e conferire la batteria esausta.

makes it clear that both items are spent/used-up.

If you said:

• Dobbiamo smaltire l'olio esausto e conferire la batteria.

that would still be grammatical, but it would no longer explicitly say that the battery is dead/spent.

So the repetition is useful and natural here.

Yes. A natural English translation often depends on the context.

A very literal translation might sound awkward, because verbs like smaltire and conferire are somewhat technical. So in real English, you might translate the sentence more idiomatically, for example:

• We need to dispose of the used oil and take the dead battery to the proper collection point.
• We need to get rid of the used oil properly and drop off the dead battery.

So a word-for-word translation is not always the best way to understand the Italian.

It is possible in some cases for Italian adjectives to come before the noun, but here that would be unusual.

The normal forms are:

• olio esausto
• batteria esausta

Putting esausto/a before the noun in this context would sound unnatural or marked. For waste-disposal language, the standard order is definitely noun + adjective.

Yes, smaltire is a regular -ire verb.

Its pronunciation is approximately:

• smal-TEE-re

A few present-tense forms are:

• io smaltisco
• tu smaltisci
• lui/lei smaltisce
• noi smaltiamo
• voi smaltite
• loro smaltiscono

It belongs to the group of -ire verbs that add -isc- in some forms.

Yes, conferire is also a regular -ire verb of the -isc- type.

For example:

• io conferisco
• tu conferisci
• lui/lei conferisce
• noi conferiamo
• voi conferite
• loro conferiscono

In this sentence, though, it appears in the infinitive because it follows dobbiamo:

• dobbiamo conferire

Yes, the sentence could be rearranged, although the original order is perfectly natural.

For example:

• Dobbiamo conferire la batteria esausta e smaltire l'olio esausto.

This still means the same thing. The main difference is just emphasis or flow.

Italian word order is somewhat flexible, but the original version sounds clear and standard.