yuusyoku wo tukurimasita.

を marks 夕食 as the direct object of the verb. In other words, it shows what was made.

• 夕食 = dinner
• を = object marker
• 作りました = made

So 夕食を作りました means (someone) made dinner.

作りました is the past polite form of 作る (to make), so it means made.

Compare:

• 作ります = make / will make
• 作りました = made

So this sentence is talking about something that has already happened: made dinner.

The dictionary form is 作る.

Here is the basic pattern:

• 作る = plain dictionary form
• 作ります = polite non-past
• 作りました = polite past

This is a very common verb pattern in Japanese.

Japanese often leaves out the subject when it is understood from context.

So 夕食を作りました could mean:

• I made dinner
• He made dinner
• She made dinner
• We made dinner

The listener usually understands who did it from the situation. This omission is extremely common in natural Japanese.

Although it is written with the kana を, in modern Japanese it is usually pronounced o.

So:

• 夕食を作りました
• is pronounced roughly yuushoku o tsukurimashita

The kana を is mainly used as a particle, not with the old wo pronunciation in everyday speech.

You are right: normal Japanese writing usually does not use spaces.

So the natural written sentence is:

夕食を作りました。

Spaces are often added in textbooks or beginner materials to make the parts easier to see:

• 夕食 | を | 作りました

But in ordinary Japanese, the sentence would normally be written without spaces.

Yes. 夕食 is a standard and fairly neutral word meaning evening meal / dinner.

You may also see:

• 晩ご飯（ばんごはん） = dinner, evening meal
• 夜ご飯（よるごはん） = dinner, more casual in some contexts

Compared with those, 夕食 can sound a bit more formal or neutral, but it is very common and natural.

Yes, but the nuance changes.

• 夕食を作りました = simply states made dinner
• 夕食は作りました = puts focus or contrast on dinner

For example, は might suggest something like:

• As for dinner, I made it
• I made dinner, at least
• I made dinner (though maybe not something else)

So を is the most straightforward choice when you are just saying what you made.

作る is a godan verb (also called a u-verb).

That is why its forms change like this:

• 作る → dictionary form
• 作ります → polite non-past
• 作りました → polite past
• 作らない → plain negative
• 作って → te-form

This is a very useful verb to learn because it appears often in everyday Japanese.

作る means to make in a broad sense. Depending on context, it can mean:

• make food
• make something by hand
• create something
• produce something

In this sentence, because the object is 夕食 (dinner), the natural English translation is often made dinner or cooked dinner.

So the Japanese verb itself is broad, but the object tells you what kind of making it is.

Yes. 作りました is polite Japanese because it uses the -ます form.

Compare:

• 夕食を作りました。 = polite
• 夕食を作った。 = plain / casual

You would use 作りました in polite conversation, with people you do not know well, with teachers, coworkers in many situations, and so on.

The basic structure is:

noun + を + verb

In this case:

• 夕食 = noun
• を = object marker
• 作りました = verb

So the order is:

Dinner + object marker + made

Japanese verbs usually come at the end of the sentence, which is one of the biggest differences from English.