ضروري تنقع البقعة قبل دورة الغسيل.

Here, تنقع most likely means you soak, addressed to one person. In many learning materials and instructions, the masculine singular form is used as the default.

But this form can also mean she soaks in a different context, so the surrounding meaning matters.

Related forms:

• تنقع = you soak (masc. singular) / she soaks
• تنقعي = you soak (fem. singular)
• تنقعوا = you soak (plural)

البقعة means the spot or the stain. In a laundry context, it almost certainly means the stain on the clothing.

The الـ at the beginning means the, so it is referring to a specific stain, not just any stain.

Because نقع means to soak, and the thing being soaked comes directly after the verb. So تنقع البقعة is simply you soak the stain.

English also does this:

• soak the stain
• remove the stain

So the structure is not very different here.

قبل means before.

دورة الغسيل means the wash cycle or the washing cycle. This is a noun + noun structure called idafa:

• دورة = cycle
• الغسيل = the washing / the laundry

So literally it is before the cycle of washing, which in natural English is before the wash cycle.

It is understandable, and it works well in instructions, labels, or appliance-related language. But it can sound a bit formal or standard.

In more casual spoken Levantine, people might say things like:

• قبل الغسلة
• قبل ما تحطّها بالغسالة
• قبل ما تغسلها

So the given sentence is fine, but slightly more formal than everyday conversation.

Yes. لازم is very common in Levantine and often feels more everyday than ضروري.

So you could also say:

• لازم تنقع البقعة قبل دورة الغسيل

Both are understandable. ضروري can sound a bit like it’s essential, while لازم often sounds like must / need to.

You would change the verb form:

• To a man: ضروري تنقع البقعة قبل دورة الغسيل
• To a woman: ضروري تنقعي البقعة قبل دورة الغسيل
• To a group: ضروري تنقعوا البقعة قبل دورة الغسيل

The rest of the sentence stays the same.

A rough pronunciation would be:

daruuri tenʔaʿ el-boʔʿa ʔabl dawret el-ghasiil

In many Levantine accents, ق is pronounced as a glottal stop ʔ, especially in everyday speech. That is why both تنقع and البقعة may sound like they have a little catch in the throat.