Mater in mortario allium et salem miscet, et pistillo parvo lente utitur.

Latin word order is much freer than English word order, because the endings show how words function. Putting mater first gives it emphasis as the topic: Mother is the one doing these actions.

A very neutral English-style order might be something like:

Mater allium et salem in mortario miscet...

But the original sentence is perfectly natural Latin.

The preposition in can take either the ablative or the accusative, depending on the meaning.

• in + ablative = in/on a place, showing location
• in + accusative = into/onto a place, showing motion toward it

Here in mortario means in the mortar, so it shows location, not motion. That is why mortario is ablative.

Mortario is ablative singular.

Its dictionary form is mortarium, mortarii (neuter), meaning mortar.

So:

• nominative singular: mortarium
• ablative singular: mortario

They are the direct objects of miscet (mixes), so they are in the accusative case.

• allium = accusative singular of allium (garlic)
• salem = accusative singular of sal (salt)

Latin marks direct objects by case endings rather than by word order alone.

Because sal belongs to the third declension, not the second.

Its basic forms are:

• nominative singular: sal
• accusative singular: salem

So in this sentence, since salt is the direct object, Latin uses salem.

They do two different joining jobs:

• allium et salem = garlic and salt
• miscet, et... utitur = she mixes, and... uses

So the first et joins two nouns, and the second et joins two verbs or actions.

Miscet is present tense, third person singular, from misceo, miscere, meaning to mix.

So miscet means:

• she mixes
• or sometimes is mixing, depending on context

Since the subject is mater, English naturally translates it as she mixes or mother mixes.

Because utor, uti, usus sum is a deponent verb.

A deponent verb:

• has passive-looking forms
• but an active meaning

So utitur looks passive in form, but it means she uses, not she is used.

This is a very common thing for learners to ask, because it feels backward from English.

Because utor takes its object in the ablative case, not the accusative.

So:

• pistillo = with a pestle
• parvo = small, agreeing with pistillo

Together, pistillo parvo utitur means she uses a small pestle.

This is one of the important things to memorize about utor:

• utor + ablative

Because adjectives in Latin agree with the nouns they describe in:

• gender
• number
• case

Here:

• pistillo is masculine, singular, ablative
• parvo is also masculine, singular, ablative

That matching tells you that parvo describes pistillo: a small pestle.

Lente is an adverb, meaning slowly.

It tells us how she uses the pestle.

So:

• pistillo parvo = with a small pestle
• lente = slowly
• utitur = she uses

Together: she uses a small pestle slowly.

Here it is an adverb.

An adjective would describe a noun, but lente describes the verb utitur. It tells us the manner of the action.

A beginner may confuse it with an adjective form, but in this sentence its function is clearly adverbial: slowly.

Yes. Latin adverbs often have flexible placement.

For example, these would still make sense:

• Mater in mortario allium et salem miscet, et lente pistillo parvo utitur.
• Mater in mortario allium et salem miscet, et pistillo lente parvo utitur.
  (less neat stylistically)

The original placement, pistillo parvo lente utitur, is natural and clear.

Classical Latin has no articles equivalent to English the or a/an.

So:

• mater can mean mother or the mother
• mortario can mean in a mortar or in the mortar
• pistillo parvo can mean with a small pestle or with the small pestle

The exact sense depends on context.

A learner could take away several useful points:

• in + ablative for location: in mortario
• direct objects in the accusative: allium et salem
• utor is a deponent verb
• utor takes the ablative: pistillo parvo utitur
• adjective agreement: parvo matches pistillo
• lente is an adverb
• Latin word order is flexible

So this short sentence is actually a very good review of several core Latin features.