Puella strigili utitur, sed mater dicit se in frigidarium statim intrare nolle.

Because utor, uti, usus sum is a deponent verb. Deponent verbs use passive-looking forms, but they have an active meaning.

So:

• utitur looks passive in form
• but it means he/she uses, not is used

That is why Puella strigili utitur means The girl uses a strigil.

Because Latin utor does not take a direct object in the accusative. It takes the ablative.

So:

• English: use a strigil
• Latin: utitur strigili

This is just something you learn with the verb utor: it governs the ablative.

A learner may find this strange at first, but it is normal Latin usage. A few other verbs also do this, such as fruor and vescor.

It is ablative singular.

The dictionary form is strigilis. In this sentence, the form strigili is the ablative singular used after utitur.

So the structure is:

• puella = nominative subject
• strigili = ablative with utitur

This is a very common Latin construction called indirect statement or accusative and infinitive.

Instead of saying something like:

• Mother says that ...

Latin often says:

• mater dicit se ... nolle

Literally, the pattern is:

• dicit = says
• se = the subject of the reported statement, put in the accusative
• nolle = infinitive verb of the reported statement

So Latin does not need a separate word for that here.

Because in a Latin indirect statement, the subject of the reported clause goes into the accusative.

So even though se is logically the subject of nolle and intrare, it appears in the accusative because of the construction after dicit.

This is one of the big differences between Latin and English:

• English: she does not want to enter
• Latin: se ... intrare nolle

Here, se refers to mater, the subject of dicit.

So the meaning is:

• the mother says that she herself does not want to enter the frigidarium immediately

A native English speaker may first assume that she means the girl, but Latin se normally points back to the subject of the main verb introducing the statement, here mater.

If Latin wanted to say that the mother says the girl does not want to enter, it would more naturally use eam or puellam, not se.

Because they do different jobs.

• nolle is the main verb of the indirect statement: to not want
• intrare depends on nolle: to enter

So the phrase means:

• to not want to enter

In English we also do something similar:

• she does not want to enter

Latin simply puts both verbs in the infinitive because the whole reported statement is being expressed as an indirect statement.

Because nolo, nolle is the normal Latin verb meaning not want or be unwilling.

It is an established verb in its own right, built historically from non + volo, but you should treat it as a normal vocabulary item:

• volo = I want
• nolo = I do not want
• nolle = not to want

So se ... intrare nolle is the standard way to say that she does not want to enter.

Because in with the accusative usually shows motion into a place.

So:

• in frigidarium intrare = to enter into the frigidarium
• in frigidario would usually mean in the frigidarium, expressing location rather than movement

Since intrare involves going into the room, the accusative is the natural choice.

Statim means immediately, at once, or right away. It modifies the idea of intrare nolle: the mother says she does not want to enter immediately.

In smoother English, you would usually place it near enter or at the end:

• she does not want to enter the frigidarium immediately
• she does not want to go into the frigidarium right away

Latin word order is more flexible, so statim can sit comfortably before intrare.

Latin word order is flexible, but not random. The grammar is shown mostly by endings, so the author can arrange words for emphasis or style.

This sentence is fairly natural:

• Puella strigili utitur
• sed mater dicit se in frigidarium statim intrare nolle

A few points:

• sed mater brings in the contrast: but the mother...
• se ... nolle frames the reported statement
• putting nolle at the end is very normal Latin style

You could rearrange parts of the second clause without changing the basic meaning, for example:

• mater dicit se statim in frigidarium intrare nolle

The endings keep the grammar clear.