yakuzaisi ni syohousen wo misetara, nomikata wo teinei ni setumeisite kuremasita

Because 見せる usually follows the pattern:

A に B を 見せる
= show B to A

So in this sentence:

• 薬剤師に = to the pharmacist
• 処方箋を = the prescription
• 見せたら = when/after I showed (it)

The に marks the person the prescription was shown to.

Because 処方箋 is the thing being shown, and with 見せる, the thing shown is marked by を.

So:

• 薬剤師に = to the pharmacist
• 処方箋を = the prescription
• 見せる = to show

This is a very common pattern:

• 先生に宿題を見せる = show the homework to the teacher
• 友達に写真を見せる = show the photo to a friend

Here, 見せたら is best understood as when/after I showed (it), not a hypothetical if.

たら can mean several things depending on context:

• if
• when
• after doing

In this sentence, it describes a sequence of events:

1. I showed the prescription to the pharmacist.
2. Then the pharmacist explained how to take the medicine.

So 見せたら means something like:

• when I showed it
• after I showed it

This use of たら is very common when one action leads naturally to the next.

Japanese often leaves the subject unstated when it is clear from context.

Here, the natural interpretation is:

• (I) showed the prescription to the pharmacist
• the pharmacist explained how to take it to me

So the hidden subjects are probably:

• 見せたら → I
• 説明してくれました → the pharmacist

A fuller version could be:

私が薬剤師に処方箋を見せたら、薬剤師が飲み方を丁寧に説明してくれました。

But Japanese normally omits repeated or obvious subjects.

飲み方 literally means way of drinking/taking.

It is made from:

• 飲み = the stem of 飲む (to drink / to take, for medicine)
• 方 = way of doing something

So 飲み方 means:

• how to take it
• the way to take the medicine
• dosage instructions / directions for use depending on context

This pattern is very common:

• 食べ方 = how to eat
• 使い方 = how to use
• 書き方 = how to write

In this sentence, 飲み方 clearly refers to how to take the medicine.

Because 丁寧 is modifying the verb 説明して, not a noun.

• 丁寧な + noun

  • 丁寧な説明 = a careful/polite explanation

• 丁寧に + verb

  • 丁寧に説明する = to explain carefully/politely

In this sentence, the pharmacist explained in a careful way, so the adverb form 丁寧に is used.

くれました adds the nuance that the pharmacist did the action for me / to my benefit.

Compare:

• 説明しました = explained
• 説明してくれました = explained for me / kindly explained to me

So ～てくれる often means someone does something that benefits the speaker (or the speaker’s in-group).

In this sentence, it gives a natural feeling like:

• The pharmacist kindly explained it to me
• The pharmacist took the time to explain it for me

It is not just about the action happening; it also shows the speaker’s perspective.

Not necessarily especially kind, but it often gives a warm or appreciative nuance.

～てくれる does two things:

1. shows that someone did something for the speaker’s benefit
2. often makes the sentence sound more personal or appreciative

So 説明してくれました can feel like:

• explained it to me
• helpfully explained it to me
• was kind enough to explain it to me

The kindness may be explicit, but in this sentence that feeling is also strengthened by 丁寧に.

Because the sentence is describing a completed past event.

• 見せたら = when/after I showed
• 説明してくれました = explained for me

This is a normal way to recount something that happened, such as at a pharmacy or doctor’s office.

Even though たら contains a past form (見せた), it does not mean had shown in an English grammatical sense. It is simply the form used before ら.

Yes, 飲み方を説明する is natural.

Both are possible:

• 飲み方を説明する = explain how to take it
• 飲み方について説明する = explain about how to take it

The version with を is more direct and compact. It treats 飲み方 as the content being explained.

This kind of pattern is common:

• ルールを説明する = explain the rules
• 使い方を説明する = explain how to use it
• 理由を説明する = explain the reason

So 飲み方を説明してくれました is very natural Japanese.

Yes, in a way. The sentence does not explicitly say the way to take the medicine, but that meaning is understood from context.

Since the speaker showed a 処方箋 to a 薬剤師, 飲み方 naturally means:

• how to take the prescribed medicine
• dosage/use instructions for that medicine

Japanese often leaves out information that is obvious from the situation.

Yes, exactly. That is a very natural reading.

～たら often connects an action with the result that followed:

• 薬剤師に処方箋を見せたら、…
  = When/after I showed the prescription to the pharmacist, … = Once I showed the prescription to the pharmacist, …

It can feel like one event triggered the next. In this context, that makes perfect sense: showing the prescription led to the explanation.

It is polite, standard Japanese.

Signs of politeness include:

• 説明してくれました instead of plain 説明してくれた
• no rough or casual wording
• 丁寧に also contributes a polite, respectful tone in meaning

This is the kind of sentence you could naturally use when politely describing what happened at a pharmacy.

Both are possible depending on context, because 丁寧に can mean:

• carefully
• politely
• thoroughly

In this sentence, the most natural nuance is probably carefully / clearly / thoroughly, since it is about medicine instructions.

So the sense is something like:

• The pharmacist carefully explained how to take it.
• The pharmacist explained the dosage instructions clearly and politely.

Japanese 丁寧に often covers both manner and attitude at the same time.