Learn Hardcore Japanese: kare ha intaanetto de nihon no sizen ya mori no syasin wo sagasuno ga suki desu. - He likes searching on the internet for photos of Japanese nature and forests.

So the sentence literally means:
“As for him, searching for photos of Japanese nature and forests on the Internet is liked.”
→ natural English: “He likes searching for photos of Japanese nature and forests on the Internet.”

What does インターネットで mean, and why is で used?

インターネットで means “on the Internet” or “via the Internet.”

で here marks the place or means where/how an action is done:

図書館で勉強します。 – I study at the library.
バスで行きます。 – I go by bus. (means of transport)
インターネットで探します。 – I search on the Internet. (means/place of searching)

So インターネットで = using the Internet as the medium.

What is 探すの in 探すのが好きです? Why is の there?

探すの is a verb phrase turned into a noun.

探す = to search
の = nominalizer (turns the verb phrase into a “thing”)

探すの therefore means “searching” (the activity of searching).

The pattern is:

[dictionary-form verb + の] が好きです
- 本を読むのが好きです。 – I like reading books.
- 音楽を聞くのが好きです。 – I like listening to music.
- 写真を探すのが好きです。 – I like searching for photos.

Without の, 探すが好きです would be ungrammatical; 探す alone cannot be the subject of 好き.

What’s the difference between ～のが好きです and ～ことが好きです? Could we say 探すことが好きです?

Yes, you can say:

インターネットで日本の自然や森の写真を探すことが好きです。

The meaning is basically the same: “(He) likes searching for photos…”

Differences (usually subtle):

～のが好きです
- Often sounds a bit more casual / natural in everyday speech.
- Can feel a little more concrete, immediate.
～ことが好きです
- Slightly more formal or abstract.
- Common in writing or more “textbook-like” language.

In this sentence, 探すのが好きです is very natural; 探すことが好きです is also correct but feels a bit more formal or “stiff” in everyday conversation.

Why is 彼 followed by は and not が (why not 彼がインターネットで…好きです)?

は marks the topic (what we’re talking about), while が marks the grammatical subject of the verb/adjective phrase.

In this sentence, the real subject of 好き is the activity “searching for photos…” (探すの), so that part takes が.

彼は – as for him (topic)
探すのが好きです – searching is liked

If you say 彼がインターネットで…探すのが好きです, you are now presenting 彼 as the subject that contrasts with someone else (like “HE, as opposed to others, is the one who likes it”). It’s possible in specific contexts, but the neutral, default wording here is with 彼は.

How is the phrase 日本の自然や森の写真 structured? What exactly modifies what?

The most natural reading is:

日本の (自然や森) の写真

So:

自然や森 – nature and forests
日本の自然や森 – Japanese nature and forests
日本の自然や森の写真 – photos of Japanese nature and forests

So the whole block 日本の自然や森の modifies 写真. It’s not “photos of Japanese nature and (some) forest,” but rather “photos of Japanese nature and Japanese forests.”

What does the particle や do in 自然や森? How is it different from と?

や is a non-exhaustive “and”: AやB = A, B, and things like that.

自然や森 ≈ “nature, forests, and similar things”
It suggests examples, not a complete list.

と is a more exact, exhaustive “and”:

自然と森 – nature and forests (specifically those two, as a set)

So 日本の自然や森の写真 implies he likes searching for photos of Japanese nature, forests, and probably other similar natural scenery too.

Why is 写真 marked with を?

を marks the direct object of the verb.

写真を探す – to search for photos

In this sentence:

Verb: 探す = to search for
Direct object: 日本の自然や森の写真 = photos of Japanese nature and forests
So we have 日本の自然や森の写真を探す – to search for photos of Japanese nature and forests.

Then that whole action phrase gets turned into a noun phrase with の:

日本の自然や森の写真を探すの – searching for photos of Japanese nature and forests

Why can’t we just say 探すが好きです without の?

Because 探す (the plain verb) cannot directly act as a noun-like subject of 好き in this pattern. You need something that functions as a noun phrase, which is created by の (or こと).

Correct patterns:

写真を探すのが好きです。
写真を探すことが好きです。

Incorrect:

写真を探すが好きです。 ✗

So の is essential here to nominalize the verb phrase.

Could the word order be 彼は日本の自然や森の写真をインターネットで探すのが好きです instead? Is that okay?

Yes, that word order is also grammatical and natural:

彼は日本の自然や森の写真をインターネットで探すのが好きです。

Japanese word order is relatively flexible as long as:

The particles stay attached to the right words.
The verb comes at (or near) the end of its clause.

Both:

インターネットで日本の自然や森の写真を探すのが好きです。
日本の自然や森の写真をインターネットで探すのが好きです。

sound natural. The nuance difference is tiny; the first puts slightly more early focus on “on the Internet,” the second on “photos of Japanese nature and forests,” but in conversation they’re effectively the same.

What does 自然 mean in this context? Is it always “nature”?

In this sentence, 自然 means “nature” as in natural scenery / the natural environment:

mountains, rivers, forests, seas, fields, etc.

自然 can also mean “naturalness” or “spontaneity” in other contexts (e.g. 自然な日本語 = natural Japanese), but here, combined with 森 and 写真, it clearly refers to outdoor nature scenery.

What is the nuance of 森 here? How is it different from other “forest” words?

森 means “forest / woods” in a fairly everyday, neutral way.

Other related words:

林（はやし） – grove, small woods, thicket
森林（しんりん） – forest in a more technical / formal sense (used in environmental science, government terms, etc.)

In this sentence, 森 gives a natural, scenic image – forests as part of beautiful nature photos, not a technical “forest resource.”

Why is 好き used like an adjective and not a verb “to like”?

In Japanese, 好き is an adjectival noun (na-adjective), not a verb.
The structure is:

X が好きです。 – X is liked / I like X.
音楽が好きです。 – I like music.
旅行が好きです。 – I like traveling.

Here:

インターネットで日本の自然や森の写真を探すの – the activity
…が好きです – is liked

So grammatically it’s:

“As for him, [searching for photos…] is liked.”

There is a verb 好む（このむ） = to like, to be fond of, but it is more formal / literary and not used in this everyday pattern.

How would this sentence change in casual speech?

In casual (informal) speech, you would typically:

drop です → use だ or nothing
possibly drop 彼は if context is clear

Examples:

インターネットで日本の自然や森の写真を探すのが好きだ。
インターネットで日本の自然や森の写真を探すのが好き。

If the subject is understood from context, you might just say:

日本の自然や森の写真を探すのが好き。 – “I like searching for photos of Japanese nature and forests.”

Can we omit 彼は? How is the meaning affected?

Yes, you can omit 彼は, especially if it’s already clear who you’re talking about from context. Then you just have:

インターネットで日本の自然や森の写真を探すのが好きです。

In Japanese, subjects (and even topics) are very often dropped when they are understood. The English translation would still usually use “He” or “I” depending on the context, even though Japanese doesn’t say it explicitly.