syokki wo arauno ha mendou desu ga, tabeta ato sugu aratta hou ga ii desu.

Here, の turns the verb phrase 食器を洗う into a noun-like expression.

• 食器を洗う = to wash the dishes
• 食器を洗うの = washing the dishes
• 食器を洗うのは面倒です = Washing the dishes is a hassle.

This の is called a nominalizer. It lets an action behave like a thing you can talk about.

は marks 食器を洗うの as the topic.

So the sentence structure is basically:

• 食器を洗うのは = as for washing the dishes
• 面倒です = it is troublesome / a hassle

Together:

• 食器を洗うのは面倒です = As for washing dishes, it’s a hassle.

In natural English, we usually just say Washing the dishes is a hassle.

面倒 means something like:

• troublesome
• bothersome
• a hassle
• a pain

So 面倒です means it is troublesome or it’s a hassle.

In this sentence, it describes the action of washing dishes:

• 食器を洗うのは面倒です = Washing dishes is a hassle.

Here が means but, but it often sounds softer and more natural than a strong English but.

So:

• 面倒ですが、... = It’s a hassle, but...

This が connects the two ideas:

1. Washing dishes is annoying.
2. It’s better to wash them right after eating.

So the speaker is acknowledging one fact, then giving advice anyway.

With あと meaning after, Japanese often uses the past/plain form of a verb before it to mean after doing something.

So:

• 食べたあと = after eating
• 見たあと = after seeing
• 終わったあと = after finishing

Even though English uses -ing sometimes, Japanese uses the past form here.

So 食べたあと does not mean after ate in a literal English sense. It is just the normal Japanese grammar for after eating.

すぐ means:

• immediately
• right away
• soon

In this sentence, it means the dishes should be washed right after eating, without waiting too long.

So:

• 食べたあとすぐ = right after eating

It emphasizes that the washing should happen promptly.

The pattern verb in past form + ほうがいい is a very common way to give advice.

So:

• 洗ったほうがいい = you’d better wash them / it’s better to wash them

Even though 洗った is past form, this expression is not talking about the past. It is a fixed grammar pattern for recommendation.

Common examples:

• 早く寝たほうがいい = You should go to bed early.
• 病院に行ったほうがいい = You should go to the hospital.
• すぐ洗ったほうがいい = You should wash them right away.

So this is one of those cases where the past form has a special grammatical use.

Not exactly. It sounds more like advice or a recommendation than a direct order.

• 洗いなさい = Wash them.
  This is a direct command.
• 洗ってください = Please wash them.
  This is a polite request.
• 洗ったほうがいい = You should wash them / It’s better to wash them.
  This is advice.

So in this sentence, the speaker is not bossing someone around harshly. They are giving practical advice.

They are in different grammar patterns.

1. 食器を洗うのは

Here 洗う is in dictionary form because it is simply describing the action:

• 食器を洗う = to wash the dishes
• 食器を洗うの = washing the dishes

2. 洗ったほうがいい

Here 洗った is in past form because the pattern past form + ほうがいい means should / had better.

So the difference is not about time. It is about grammar:

• dictionary form + の = turns the action into a noun-like phrase
• past form + ほうがいい = gives advice

Japanese often leaves out the subject when it is clear from context or when the statement is general.

So this sentence could mean something like:

• Washing dishes is a hassle, but you should wash them right after eating.
• Washing dishes is a hassle, but it’s best to wash them right after eating.
• Washing dishes is a hassle, but people should wash them right after eating.

In English, we usually need to choose a subject. In Japanese, it is often omitted.

Yes, 食器を洗うことは面倒です is grammatically possible, but の sounds more natural here.

Very roughly:

• の often feels more direct, concrete, or close to an actual action
• こと can sound a bit more formal or abstract

So:

• 食器を洗うのは面倒です = very natural
• 食器を洗うことは面倒です = understandable, but slightly less natural in everyday speech

For a sentence about a familiar everyday action like washing dishes, の is the usual choice.

Literally, ほう means side or direction.

In older or more literal logic, 洗ったほうがいい is like saying:

• The side of washing is better

But in modern Japanese, you should learn verb past + ほうがいい as a set expression meaning:

• should do
• it’s better to do

So while the literal meaning can be interesting, the important thing is the whole pattern.

食器 means tableware / dishes / eating utensils in a broad sense. It can include:

• plates
• bowls
• cups
• other items used for eating

So 食器を洗う is a natural general way to say wash the dishes.

If you used 皿 instead, that would focus more specifically on plates:

• 皿を洗う = wash the plates

But in English, wash the dishes usually means all the dirty tableware, so 食器 fits well.

It is polite because it uses です:

• 面倒です
• いいです

A casual version might be:

• 食器を洗うのは面倒だけど、食べたあとすぐ洗ったほうがいい。

So the original sentence is appropriate for polite conversation or standard written Japanese.