Learn Hardcore Japanese: syuumatu ha tosyokan toka kouen toka de nihongo wo benkyousimasu. - On weekends I study Japanese at places like the library or the park.

週末は日本語を勉強します。
→ “On weekends (in general), I study Japanese.” (habit, general rule)
週末に日本語を勉強します。
→ “I’ll study Japanese on the weekend.” (a specific upcoming weekend, depending on context)

Using は here emphasizes that when it’s the weekend, this is what (I) do, and it sounds like a general habit.

What does とか mean here, and how is it different from と?

In this sentence, とか is used to list examples in a loose way, similar to:

“things like A and B”
“A, B, and stuff like that”

So:

図書館とか公園とかで
≈ “at places like the library or the park (and similar places)”

By contrast, と is a more straightforward “and” for lists:

図書館と公園で
→ “at the library and the park” (just those two, more neutral)

とか often implies the list is not complete, just representative examples, and it’s somewhat casual.

Why is とか repeated after both 図書館 and 公園? Can I use it only once?

Repeating とか is common in speech when listing several examples vaguely:

図書館とか、公園とかで
“at places like the library, or the park, and so on”

Patterns you might see:

N1とかN2とか … (most explicit “A and B and things like that”)
N1とかN2で … (often still feels like “A, B, etc.”, especially in casual speech)
N1やN2で … (more neutral/formal “A and B (and possibly others)”)

So yes, you can say:

図書館とか公園で日本語を勉強します。

That still tends to feel like “library, park, etc.” in casual speech, but repeating とか makes the “etc.” feeling stronger and clearer.

Does とか here mean “or” or “and”?

It’s a bit in between from an English perspective.

Logically, it’s closer to “and things like …” / “such as …”, but Japanese uses it loosely, so it can feel like:

“at the library, or the park, or somewhere like that”
and also like
“at places like the library and the park, etc.”

The key idea: it’s an example-list marker, not strict logical “and/or”. It says: These are some examples of the kinds of places where I study.

Why do we use で after 公園とか? What does で indicate?

で marks the location where an action takes place.

図書館とか公園とかで日本語を勉強します。
→ “I study Japanese at places like the library or the park.”

Compare:

図書館に行きます。 – “I go to the library.” (に = destination)
図書館で勉強します。 – “I study in/at the library.” (で = place of action)

So here, で tells us where the studying happens.

Why is 日本語 marked with を?

を marks the direct object of a verb — the thing the action is performed on.

Verb: 勉強します – “(I) study”
Object: 日本語 – “Japanese (language)”

So:

日本語を勉強します。
→ “(I) study Japanese.”

In this structure, X を勉強します is “study X”.
You’ll see this with many verbs: 本を読む (read a book), 映画を見る (watch a movie), etc.

Can I say 日本語の勉強をします instead of 日本語を勉強します? Is there a difference?

Yes, you can, and both are natural:

日本語を勉強します。
Literally “(I) study Japanese.”
日本語の勉強をします。
Literally “(I) do Japanese study / I do the studying of Japanese.”

Nuance:

日本語を勉強します is a bit more direct and common in everyday speech.
日本語の勉強をします emphasizes the activity of studying as a noun (勉強) that you “do”.

In most contexts, they’re interchangeable in meaning.

Why is there no explicit subject like “I” (私) in the sentence?

Japanese often omits the subject when it’s clear from context. In English you must say “I study”, “he studies”, etc., but in Japanese:

If you’re talking about yourself, and the conversation is about your habits, it’s understood that the subject is “I”.
So (私は)週末は図書館とか公園とかで日本語を勉強します。
is usually just said as
週末は図書館とか公園とかで日本語を勉強します。

If you need to be explicit (for contrast or clarity), you can say:

私は週末は図書館とか公園とかで日本語を勉強します。
“As for me, on weekends, I study Japanese at places like the library and the park.”

Why is the verb in the ます form (勉強します) instead of the dictionary form 勉強する?

勉強します is the polite form; 勉強する is the plain (dictionary) form.

勉強します – used in polite conversation, with people you’re not close to, in class, etc.
勉強する – used with friends, family, casual writing, or as dictionary form.

In a textbook sentence or neutral explanation of your routine, the ます-form is standard. A casual version with a friend might be:

週末は図書館とか公園とかで日本語を勉強する。

Can the word order be changed, like putting 日本語を earlier in the sentence?

Yes, Japanese word order is fairly flexible as long as the verb goes at the end and particles stay with their words.

Common variations:

週末は図書館とか公園とかで日本語を勉強します。
週末は日本語を図書館とか公園とかで勉強します。

Both are grammatically fine. The first is more natural, putting the place information before the object. But the meaning doesn’t really change.

You must keep:

週末は
図書館とか公園とかで
日本語を
勉強します

together as units (word + particle).

What is the nuance of using 週末は instead of just 週末?

Without any particle, 週末 on its own would sound incomplete. は turns it into a topic:

週末は – “As for weekends / On weekends…”

This gives the sentence a habitual, general feeling: “When it comes to weekends, I do X.”
If you used 週末に instead, it would feel more like mentioning a certain weekend time rather than setting up “weekends” as a broad topic.

So 週末は … 勉強します naturally reads as “On weekends, I (usually) study …”, not just once.