الغسيل جاف، إذن نطوي الملابس.

In Arabic, the verb to be is usually not stated in the present tense.

So:

• الغسيل جاف = The laundry is dry

There is no separate present-tense is here.

Compare:

• الغسيل جاف = the laundry is dry
• كان الغسيل جافًّا = the laundry was dry
• سيكون الغسيل جافًّا = the laundry will be dry

This is a very common feature of Arabic nominal sentences.

Because جاف here is the predicate of the sentence, not an adjective directly attached to the noun.

There is an important difference:

• الغسيل جاف = The laundry is dry
• الغسيل الجاف = the dry laundry

So:

• in الغسيل جاف, جاف is telling you something about الغسيل
• in الغسيل الجاف, الجاف is describing which laundry you mean

A native English speaker often expects both words to be definite, but in Arabic this distinction matters a lot.

إذن means something like:

• so
• then
• therefore
• in that case

In this sentence, it connects the first idea to the result:

• الغسيل جاف، إذن نطوي الملابس
• The laundry is dry, so we fold the clothes

It is a very useful linking word in formal Arabic.

نطوي is a present-tense verb in the first person plural:

• نـ = we
• طوي = from the verb طوى = to fold

So نطوي means:

• we fold
• we are folding
• sometimes we will fold, depending on context

In this sentence, the most natural meaning is we fold or we’ll fold.

In the Arabic present tense, the first letter often tells you the subject.

For this verb family:

• أطوي = I fold
• تطوي = you fold / she folds
• يطوي = he folds
• نطوي = we fold

So the prefix نـ is the marker for we.

This comes from the verb طوى.

Its basic dictionary form is:

• طوى = to fold

Its present form is:

• يطوي = he folds
• نطوي = we fold

This type of verb is slightly irregular because it is a weak verb. The letters و and ي are part of how the verb changes form.

You do not pronounce it as three separate sounds like na-ta-wa-ya. It is pronounced more like:

• naṭwī

So the middle of the word has a consonant cluster: ṭw.

They are related, but they do not mean exactly the same thing.

• الغسيل = the laundry / the washing
• الملابس = the clothes

So the sentence is saying:

• the laundry is dry
• therefore we fold the clothes

This sounds natural because laundry refers to the washed items as a batch, while clothes refers to the actual garments.

A careful reading is:

al-ghasīl jāff, idhan naṭwī al-malābis

A few notes:

• الغسيل = al-ghasīl
• جاف = jāf or, in full grammatical pronunciation, jāffun
• إذن = idhan
• نطوي = naṭwī
• الملابس = al-malābis

Also, in الغسيل, the ل in ال is pronounced clearly, because غ is a moon letter, not a sun letter.

A fully vowelled version could be written as:

الغسيلُ جافٌّ، إذن نطوي الملابسَ.

This shows the case endings more clearly:

• الغسيلُ = subject of the nominal sentence
• جافٌّ = predicate
• الملابسَ = direct object of نطوي

In normal everyday Arabic writing, these short vowel endings are usually omitted, so you will usually see:

الغسيل جاف، إذن نطوي الملابس.

Yes. That would also be correct, but it changes the structure slightly.

• الغسيل جاف = the laundry is dry
• الملابس جافة = the clothes are dry

Why جافة there?

Because الملابس is treated as a non-human broken plural, and in standard Arabic such plurals usually take a feminine singular adjective or predicate.

So:

• الملابس جافة
• not usually الملابس جافون or anything like that

But in your original sentence, the subject is الغسيل, which is singular masculine, so جاف matches it naturally.