umi he iku mae ni, hiyakedome wo nurimasu.

Before 前に, Japanese normally uses the plain form of the verb, not the polite ます form.

So:

• 海へ行く前に = before going to the beach
• not 海へ行きます前に

This is a very common pattern:

• 寝る前に = before sleeping
• 食べる前に = before eating
• 出かける前に = before going out

Even if the main sentence is polite, the verb before 前に still stays in the plain form.

前に means before.

The structure is:

• verb dictionary form + 前に
• noun + の + 前に

In this sentence:

• 海へ行く前に = before going to the beach

So the whole sentence is:

• Before going to the beach, I put on sunscreen.

A few more examples:

• 食べる前に、手を洗います。 = Before eating, I wash my hands.
• 寝る前に、本を読みます。 = Before sleeping, I read a book.
• 旅行の前に、予約します。 = Before the trip, I make a reservation.

In this pattern, 前に is the normal set expression for before.

You can think of に as marking the time point before X. In many cases, learners should just remember 前に as a chunk.

Compare:

• 食事の前に = before the meal
• 帰る前に = before going home

You do not usually drop the に here in standard usage.

Yes, 海に行く is also correct.

Both へ and に can mark a destination with verbs like 行く.

• 海へ行く emphasizes the direction toward the beach/sea
• 海に行く marks the destination a bit more directly

In everyday speech, the difference is usually small, and both are very natural.

So these both work:

• 海へ行く前に、日焼け止めをぬります。
• 海に行く前に、日焼け止めをぬります。

日焼け止め means sunscreen or sunblock.

It is made from:

• 日焼け = sunburn / tanning
• 止め = stopper / something that prevents

So literally it is something like a sunburn-preventer.

In real life, Japanese speakers commonly say:

• 日焼け止め
• sometimes 日焼け止めクリーム if they want to be more specific

Because 日焼け止め is the direct object of ぬります.

The verb ぬる means to apply / spread / smear something on. The thing being applied is marked by を.

So:

• 日焼け止めをぬります = apply sunscreen

Other examples:

• 薬をぬります。 = I apply medicine/ointment.
• クリームをぬります。 = I put on cream.

Yes. The dictionary form is 塗る, and the polite form is 塗ります.

So this sentence could also be written as:

• 海へ行く前に、日焼け止めを塗ります。

Why use hiragana instead?

• Sometimes beginner materials use hiragana to make reading easier.
• Some verbs are also often written in hiragana in casual or simple writing.

Both are correct, but 塗ります is the standard kanji spelling.

Japanese non-past forms cover both present and future, depending on context.

Here, ぬります means something like:

• I put on sunscreen
• I will put on sunscreen
• I put on sunscreen before going to the beach

The sentence could describe:

1. a habitual action
   
   • Whenever I go to the beach, I put on sunscreen
2. a future plan
   
   • Before going to the beach, I’ll put on sunscreen

The context decides which meaning is intended.

The subject is omitted, which is very normal in Japanese.

Japanese often leaves out words like I, you, or we if they are clear from context. So this sentence could mean:

• I put on sunscreen before going to the beach
• We put on sunscreen before going to the beach
• even You should put on sunscreen before going to the beach, depending on context

In many textbook examples, English translations use I because it is the simplest natural choice.

Yes, Japanese word order is flexible as long as the grammar is clear.

These are both natural:

• 海へ行く前に、日焼け止めをぬります。
• 日焼け止めをぬります。海へ行く前に。

The first version is more standard and smooth for this kind of sentence.

You could also say:

• 海へ行く前に、日焼け止めを塗っておきます。

That sounds more like I put on sunscreen in advance before going to the beach.

No, normal Japanese is usually written without spaces.

Standard writing would be:

• 海へ行く前に、日焼け止めをぬります。

or

• 海へ行く前に、日焼け止めを塗ります。

Spaces are often added in beginner materials to make it easier to see the words and particles.

Literally, 海 means sea/ocean. But in everyday Japanese, 海に行く or 海へ行く often naturally means go to the beach / go to the seaside.

So even though the word is literally sea, the translation go to the beach is often the most natural in English.

Context matters:

• 海で泳ぐ = swim in the sea
• 海へ遊びに行く = go to the beach/seaside for fun

It is polite because the main verb is in the ます form:

• ぬります

That makes it suitable for neutral polite conversation, textbooks, and everyday respectful speech.

The casual version would be:

• 海へ行く前に、日焼け止めをぬる。

So the sentence mixes:

• plain form before 前に: 行く
• polite main verb: ぬります

That combination is completely normal in Japanese grammar.