عشر دقائق تكفي.

Because Arabic numbers from 3 to 10 show gender polarity: the number takes the opposite grammatical gender of the noun being counted.

• دقيقة (minute) is feminine
• so the form of 10 used with it is عشر
• with a masculine noun, you would use عشرة

So:

• عشر دقائق = ten minutes
• but, for example, عشرة كتب = ten books

After the numbers 3–10, the counted noun is normally:

• plural
• and genitive

So Arabic says literally something like ten of minutes, not ten minute.

That is why you get:

• singular: دقيقة = a minute
• plural after a number like 10: دقائق

Because دقائق is a non-human plural, and in Modern Standard Arabic, non-human plurals are very often treated grammatically as feminine singular for agreement.

So even though minutes is plural in meaning, the verb appears in the 3rd person feminine singular form:

• تكفي = it is enough / it suffices

This is very normal Arabic agreement:

• الكتب وصلت = the books arrived
• الأيام تمضي = the days pass
• عشر دقائق تكفي = ten minutes is enough

Because with non-human plurals, Arabic usually does not use full plural agreement. Instead, it usually uses feminine singular agreement.

So although دقائق is plural, the standard agreement is still:

• تكفي and not a plural verb form

This is one of the most important agreement rules in Arabic, and it often feels strange to English speakers at first.

In fully vocalized formal Arabic, it would typically be:

عَشْرُ دَقائِقَ تَكْفِي

Here is why:

• عشرُ is nominative, because the phrase عشر دقائق is functioning as the subject/topic of the sentence
• دقائقَ is the counted noun after 10, so it is genitive
• تكفي is the verb and keeps its normal present-tense form

A learner may expect دقائقِ with a kasra, but there is an extra rule here: دقائق is a diptote.

Because دقائق is a diptote (ممنوع من الصرف).

Many broken plurals on patterns like فعائل behave this way. A diptote:

• does not take tanwīn
• takes fatḥa instead of kasra in the genitive and accusative when indefinite

So although دقائق is genitive here, its ending is still fatḥa:

• دقائقَ

That is an advanced but very real grammar point.

It is a complete sentence.

The verb تكفي already means is enough / suffices, so Arabic does not need any extra word like is here.

English might say:

• Ten minutes is enough

Arabic expresses that directly with the verb:

• عشر دقائق تكفي

Sometimes the context makes clear enough for what, and Arabic is happy to leave that unstated if it is obvious.

Yes. That is also grammatical.

Both are possible:

• عشر دقائق تكفي
• تكفي عشر دقائق

A simple way to think about the difference:

• عشر دقائق تكفي puts ten minutes first, so it feels more like Ten minutes is enough
• تكفي عشر دقائق starts with the verb, so it feels more like Ten minutes suffice / Ten minutes will do

The meaning is very close; the difference is mostly one of structure and emphasis.

Yes, that is also possible.

• عشر دقائق تكفي uses a verb: suffices / is enough
• عشر دقائق كافية uses an adjective: sufficient / enough

Because دقائق is a non-human plural, the adjective also appears in the feminine singular form:

• كافية

So both are natural, with slightly different styles:

• عشر دقائق تكفي
• عشر دقائق كافية

Because the sentence is talking about an indefinite quantity: ten minutes, not the ten minutes.

So the phrase is naturally indefinite:

• عشر دقائق

If you added definiteness, the meaning would change or become much more context-specific.

A careful pronunciation is:

ʿashru daqāʾiqa takfī

A few notes:

• عشر begins with ʿayn (ع), a consonant English does not have
• دقائق has a hamza sound in the middle: da-qā-ʾiq
• تكفي ends in a long ī

If you are reading ordinary unvocalized Arabic, you will usually just see:

عشر دقائق تكفي

but in careful grammar-based reading, the full form is:

عَشْرُ دَقائِقَ تَكْفِي