Learn Hardcore Japanese: konya ha bunpou no hukusyuu wo sitai desu.

Using 今夜に here is unnatural. に after a time word tends to mark a specific point in time for an event (e.g., ３時に行きます), but with words like 今日 / 明日 / 今夜, you usually just say them with は (as topic) or with no particle.

What is the role of の in 文法の復習?

の is linking two nouns: 文法 (“grammar”) and 復習 (“review”).

The structure A の B often means:

“B of A” / “A’s B”

So:

文法の復習 = “review of grammar” / “grammar review”

It’s the same pattern as:

日本語の勉強 – study of Japanese
歴史の本 – a book of/about history

So の here is basically like the English “of” or a possessive link.

Why is there an を after 復習 if する is the verb?

In Japanese, many nouns can be turned into verbs with する (“to do”). These are often called suru-verbs.

復習をする = “to do review” → “to review”
勉強をする = to study
運動をする = to exercise

In this pattern, the noun (復習) is the direct object of する, so it takes the object particle を.

In your sentence:

文法の復習をしたいです。
“I want to do a review of grammar.”

You may also see:

文法を復習したいです。
Here 文法 is directly the object of 復習する (“to review”), so 復習 is being used more like a verb.

Can we drop the を and just say 文法の復習したいです?

In casual spoken Japanese, people sometimes drop を, especially when the meaning is clear.

So in informal speech, you might hear:

今夜、文法の復習したい。

This is understood, but:

文法の復習をしたいです。

is more complete and is the correct standard form, especially in writing or polite speech. For learners, it’s safer to keep the を.

What does したいです literally mean, and why is です there?

The ending ～たい attaches to the ます-stem of a verb to express “want to do ~”.

Dictionary form: する
ます-stem: し
たい-form: したい = “want to do”

So:

復習をしたい = “(I) want to do review.”

Adding です makes it polite:

したいです → polite “want to do”

Compare:

文法の復習をしたい。 – casual
文法の復習をしたいです。 – polite

The です doesn’t add meaning beyond politeness; it just makes the sentence sound more polite and complete.

Is したい always about my desire? Do I use it for other people’s wants too?

たい generally describes the speaker’s own desire.

私は今夜、文法の復習をしたいです。
Natural: “I want to review grammar tonight.”

For someone else’s desire, Japanese usually avoids directly stating another person’s inner feelings and uses forms like:

〜たがっている
- 彼は今夜、文法の復習をしたがっています。
  “He seems to want to review grammar tonight.”

or expressions like:

〜たいと言っています (he says he wants to)
〜たいそうです (I hear he wants to)

So したいです is most natural when talking about your own wish.

How do I make this sentence negative, like “I don’t want to review grammar tonight”?

Use the negative of たい, which is たくない (casual) or たくないです / たくありません (polite).

Starting from したい (“want to do”):

Negative casual: したくない – don’t want to do
Polite: したくないです or more formal したくありません

So:

今夜は文法の復習をしたくないです。
“I don’t want to review grammar tonight.”

Is the word order flexible? Can I move 今夜 or 文法の復習 around?

Yes, Japanese word order is quite flexible as long as the verb comes at the end. All of these are grammatical:

今夜は文法の復習をしたいです。
文法の復習を今夜はしたいです。
文法の復習は今夜したいです。

The nuances:

今夜は文法の復習をしたいです。
Topic is “tonight”: “As for tonight, I want to review grammar.”
文法の復習は今夜したいです。
Topic is “reviewing grammar”: “As for reviewing grammar, I want to do it tonight (rather than some other time).”

So ordering + where you put は affects what is being highlighted as the topic or contrast.

What’s the difference between 今夜, 今晩, and 今日の夜?

All three can mean “tonight,” but there are slight tendencies:

今夜（こんや）
Very common. Often used in slightly more neutral/written style, TV weather, etc.
e.g., 今夜は雨が降ります。
今晩（こんばん）
Very common too, especially in everyday speech.
e.g., 今晩、飲みに行かない？
今日の夜（きょうのよる）
Literally “this day’s night.” Used to clarify “tonight” when contrasting 昼 / 夜, or to sound a bit more explanatory.

In your sentence, you could say:

今夜は文法の復習をしたいです。
今晩は文法の復習をしたいです。
今日の夜は文法の復習をしたいです。

All are understandable and natural; 今夜 and 今晩 are most typical.

How do you read each part of the sentence, and how is は pronounced here?

Readings:

今夜 – こんや
は (topic particle) – pronounced わ, even though written with the kana は
文法 – ぶんぽう
の – の
復習 – ふくしゅう
を – を (often sounds like お)
したい – したい
です – です (often pronounced more like です with a short “u” or lightly devoiced)

So the whole sentence is:

こんやはぶんぽうのふくしゅうをしたいです。

Is 今夜は文法の復習をしたいです。 something native speakers would really say, or is it textbook-y?

It’s perfectly natural Japanese and something a native speaker could definitely say, especially in a slightly polite or neutral situation (e.g., talking to a teacher, coworker, or someone not very close).

In more casual situations, people might say:

今夜は文法の復習したい。 (drop を and です)
今夜、文法の復習しなきゃ。 (“I’ve gotta review grammar tonight.”)
今夜、文法の復習するつもり。 (“I plan to review grammar tonight.”)

But your original sentence is good, natural, and polite, not weird or “fake” Japanese.