kono aoi syatu ha watasi no kuroi suutu ni aimasu.

Because they do different jobs:

• この = this
• 青い = blue
• シャツ = shirt

So この青いシャツ means this blue shirt.

In Japanese, this order is normal:

• この + adjective + noun

Examples:

• この赤い車 = this red car
• その古い本 = that old book

青い and 黒い are い-adjectives, so they can directly modify a noun.

• 青いシャツ = a blue shirt
• 黒いスーツ = a black suit

Using just 青 or 黒 would not work the same way here.

A rough comparison:

• 青いシャツ = blue shirt
• 青のシャツ can exist in some contexts, but it feels different and is not the most basic way to say blue shirt

For a learner, the safest pattern is:

• color adjective + noun
• 青いシャツ
• 黒いスーツ

は marks the topic of the sentence.

So:

• この青いシャツは = As for this blue shirt, ...

The sentence is talking about the shirt and then saying something about it: that it matches the speaker’s black suit.

This does not always mean は is exactly the same as the English subject marker. It introduces what the sentence is about.

Because の shows possession.

• 私の黒いスーツ = my black suit

Here, 私 is modifying スーツ:

• 私 = I / me
• の = of / ’s
• 私の = my

By contrast:

• 私は = as for me / I

So 私は黒いスーツ would start a completely different sentence and would not mean my black suit.

With 合います in this meaning, に often marks the thing that something matches or suits.

So:

• この青いシャツは私の黒いスーツに合います = This blue shirt matches my black suit

Think of it like:

• X は Y に合う = X matches Y / X goes well with Y

You may also see と with similar ideas:

• X は Y と合う = X goes with Y

Both are possible in Japanese, but に合う is very common and natural here.

Here 合います means matches, goes well with, or suits.

The dictionary form is 合う.

In different contexts, 合う can mean different things, such as:

• to fit
• to suit
• to match
• to go well with

In this sentence, it is about appearance/style coordination, not about size.

So this is not saying the shirt physically fits the suit. It means the colors or style go well together.

Because 合います is the polite non-past form of 合う.

• dictionary form: 合う
• polite form: 合います

Japanese learning materials often use polite forms first because they are safe and common in everyday conversation.

A plain-style version would be:

• この青いシャツは私の黒いスーツに合う。

That is less polite and more casual.

Not exactly. Japanese non-past can refer to:

• present
• habitual
• sometimes future, depending on context

So 合います here can mean:

• matches
• will match
• goes well with

In this sentence, the natural English translation is usually present tense: matches or goes well with.

Yes, but the nuance changes.

• この青いシャツは私の黒いスーツに合います。 = As for this blue shirt, it matches my black suit.

• この青いシャツが私の黒いスーツに合います。 = This blue shirt is the one that matches my black suit.

Using が can sound more specific or contrastive, as if you are identifying which shirt matches.

Using は is more neutral if you are simply talking about the shirt.

Japanese word order is more flexible than English, but not completely free.

This sentence has a very normal order:

• topic: この青いシャツは
• target/item it matches: 私の黒いスーツに
• verb: 合います

The verb usually comes at the end.

You could rearrange some parts for emphasis, but for learners, this pattern is the best one to remember.

No. Normal Japanese is usually written without spaces.

So the standard written sentence is:

この青いシャツは私の黒いスーツに合います。

Spaces are often added in beginner materials to make the sentence easier to read.

Yes, very often, if the meaning is clear from context.

For example:

• この青いシャツは黒いスーツに合います。

This could still be understood as This blue shirt matches the black suit, and depending on context, that suit might be yours.

Japanese often omits information that is already understood. But in your sentence, 私の is included to make it explicit: my black suit.

Yes. この青いシャツ works together as one noun phrase meaning this blue shirt.

Its internal structure is:

• この modifies
• 青いシャツ

And inside that:

• 青い modifies
• シャツ

So the full chunk is:

• この青いシャツ = this blue shirt

Then は attaches to that whole phrase:

• この青いシャツは = as for this blue shirt

Grammatically, maybe, but in natural English matches or goes well with is much better.

More natural translations are:

• This blue shirt matches my black suit.
• This blue shirt goes well with my black suit.

Suits my black suit sounds unnatural in English, even though 合う can sometimes mean suit in Japanese.