hiyokebousi wo motte kuru si, suibunhokyuu mo suru.

It is read ひよけぼうし.

It is a compound noun:

• 日よけ = sunshade / protection from the sun
• 帽子 = hat

So 日よけ帽子 is literally something like sun-protection hat.

A learner may notice that 日 is read ひ here, not にち or じつ. That is normal in compounds and set expressions: kanji often have different readings depending on the word.

を marks the direct object of the verb.

Here, the verb phrase is 持ってくる, so 日よけ帽子を持ってくる means that the hat is the thing being brought.

So the structure is:

• 日よけ帽子 = the sun hat
• を = object marker
• 持ってくる = bring

English uses word order to show this, but Japanese uses particles.

Because 持つ and 持ってくる do different jobs.

• 持つ = to hold / to carry / to have
• 持ってくる = to bring

So if the idea is bring a sun hat, Japanese naturally uses 持ってくる.

Compare:

• 帽子を持つ = hold/carry a hat
• 帽子を持ってくる = bring a hat

English often uses bring, and Japanese commonly expresses that with ～てくる attached to an action verb like 持つ.

In this sentence, 持ってくる is the て-form of 持つ plus くる.

• 持つ → 持って
• くる = come

Together, 持ってくる literally means carry and come, which is why it means bring.

A useful contrast is:

• 持ってくる = bring (toward the speaker, listener, or relevant place)
• 持っていく = take (away to another place)

So if you are talking about what someone should bring to an event, 持ってくる is very natural.

し is often used to give reasons or list points.

In this sentence, it connects one point to another:

• 日よけ帽子を持ってくるし
• 水分補給もする

It gives a feeling like:

• I’ll bring a sun hat, and I’ll also stay hydrated.
• Bring a sun hat, and also make sure to drink fluids.

A key thing to know: し is often softer and more conversational than a simple rigid list. It can sound like the speaker is giving supporting points or saying for one thing... and also...

Also, し often implies there may be more unstated reasons or actions.

も means also / too.

So 水分補給もする means also hydrate or also make sure to drink fluids.

The も shows that this is an additional action, not the only one. The sentence is basically saying:

• bring a sun hat, and also
• hydrate

Without も, the sentence would still be grammatical, but も makes the additive meaning clearer.

Yes.

水分補給 is a noun meaning hydration / fluid intake / replenishing fluids, and する turns it into a verb phrase:

• 水分補給 = hydration
• 水分補給する = to hydrate / to take in fluids

This is very common in Japanese. Many Sino-Japanese nouns can combine with する to form verbs.

Other common examples:

• 勉強する = study
• 運動する = exercise
• 準備する = prepare

So 水分補給もする is structurally very normal Japanese.

Actually, both are possible:

• 水分補給する
• 水分補給をする

The version without を is very common with する-verbs and often sounds a bit smoother and more natural in everyday Japanese.

So:

• 水分補給する = perfectly normal
• 水分補給をする = also correct

A lot of learners expect every object to need を, but with noun + する combinations, Japanese often skips it.

Japanese often omits the subject when it is understood from context.

So this sentence does not explicitly say:

• I
• you
• we
• they

The subject has to be inferred from the situation.

Depending on context, it could mean things like:

• I’ll bring a sun hat and stay hydrated.
• You should bring a sun hat and stay hydrated.
• We’ll bring a sun hat and stay hydrated.

This is very normal in Japanese. English usually requires a subject, but Japanese often leaves it out when it is obvious.

It is in the plain style, not the polite ます style.

• くる instead of きます
• する instead of します

That makes it sound casual, neutral, or like a note/reminder depending on context.

A more polite version would be:

• 日よけ帽子を持ってきますし、水分補給もします。

Or, if giving advice politely:

• 日よけ帽子を持ってきて、水分補給もしてください。

So the original sentence is grammatically plain and likely depends on context for its exact tone.

No. Standard Japanese is normally written without spaces.

So this would usually appear as:

日よけ帽子を持ってくるし、水分補給もする。

Learning materials often insert spaces to make the structure easier to see, especially for beginners. That is helpful for study, but it is not how Japanese is usually written in books, messages, or signs.