aratta syatu wo hangaa ni kakete, beranda ni hosimasu.

Because Japanese puts noun modifiers before the noun.

So 洗ったシャツ means the shirt that was washed or the washed shirt.

Here, 洗った is the plain past form of 洗う and it is modifying シャツ. It does not mean the whole sentence is in the past. It just tells you the shirt is already in a washed state by the time the main action happens.

Because in this sentence, washing is not being presented as one of the main connected actions. Instead, it is just describing which shirt we are talking about.

• 洗ったシャツ = the washed shirt
• シャツを洗って、ハンガーにかけて… = wash the shirt, then put it on a hanger...

So if the speaker wanted to describe the full sequence from washing onward, they would more likely say:

シャツを洗って、ハンガーにかけて、ベランダに干します。

But the given sentence starts from the shirt after it has already been washed.

を marks シャツ as the direct object.

It is the thing being acted on:

• put the shirt on a hanger
• hang the shirt out on the balcony

In Japanese, one object can often be understood with more than one verb in a chain like this, so シャツを naturally carries through both かけて and 干します.

The て-form is being used to connect actions in sequence.

So:

• ハンガーにかけて
• ベランダに干します

means something like:

• put it on a hanger, and then hang it out on the balcony

Only the last verb usually shows the sentence’s tense and politeness clearly. That is why 干します is the final polite verb, while かけて is just the connecting form.

They are related, but not the same.

• ハンガーにかける = to put/hang something on a hanger
• 干す = to hang something out to dry / to dry laundry

So the sentence is not repeating the same idea twice.

It is more like:

1. put the washed shirt on a hanger
2. hang it out on the balcony to dry

That is a very natural combination in Japanese.

Because each に marks a different kind of target/location.

• ハンガーにかける: the hanger is the thing the shirt is being placed onto
• ベランダに干す: the balcony is the place the shirt is being hung out at / onto

In both cases, に shows where the shirt ends up.

A learner may wonder whether ベランダで is possible. Sometimes で can be used for the place where an action happens, but ベランダに干す is very natural because it emphasizes putting/hanging the laundry there.

Japanese nouns usually do not show singular/plural the way English does.

So シャツ can mean:

• shirt
• shirts

Context decides.

In isolation, many learners will read it as a shirt, but it could absolutely refer to shirts in the right situation. Japanese often leaves number unspecified unless it matters.

This is normal Japanese grammar.

• 干します is the final verb, so it carries the polite ending ます
• かけて is a connecting form, so it does not take ます
• 洗った is inside a noun-modifying clause, and clauses that modify nouns normally use plain forms, even in polite speech

So a sentence can be polite overall even if parts inside it are plain:

• 洗ったシャツ — plain form modifying a noun
• 干します — final polite verb

That is completely standard.

The subject is omitted because it is understood from context.

Japanese often leaves out words like:

• I
• we
• she
• they

if they are already obvious.

So depending on context, this could mean:

• I hang the washed shirt on a hanger and dry it on the balcony
• We hang the washed shirt...
• or even a general instruction-like statement

The omitted subject is one of the most common features of natural Japanese.

干します is in the Japanese non-past form.

That means it can mean either:

• present / habitual: I hang washed shirts on the balcony
• future / next action: I’ll hang it on the balcony

Japanese often does not separate present and future as strictly as English does. The meaning depends on context.

So this sentence could describe:

• a routine
• what the speaker is about to do
• a general method

A helpful way to break it down is:

• 洗ったシャツを = the washed shirt(s)
• ハンガーにかけて = put it on a hanger
• ベランダに干します = hang it out on the balcony to dry

Japanese often places:

1. descriptions before the noun
2. particles after nouns
3. the main verb near the end

So even if the word order feels very different from English, the sentence is built in a very regular Japanese way.