المصادقة الثنائية وقفل البصمة جاهزان.

Because this is a present-tense nominal sentence in Arabic. In that kind of sentence, Arabic normally does not use a separate word for am / is / are.

So the structure is basically:

• المصادقة الثنائية وقفل البصمة = the subject
• جاهزان = the predicate (ready)

Literally, it is closer to:

• Two-factor authentication and fingerprint lock ready.

If you wanted the past or future, Arabic would usually add a verb such as كانا (they two were) or سيكونان (they two will be).

Because the sentence is talking about exactly two things:

1. المصادقة الثنائية
2. قفل البصمة

When Arabic has two coordinated items as the subject, the predicate can appear in the dual. So جاهزان means ready for two things.

It is also masculine because the two nouns are mixed in gender:

• المصادقة is feminine
• قفل is masculine

With mixed gender, Arabic normally defaults to the masculine form. So:

• not جاهزة (singular feminine)
• not جاهزتان (dual feminine)
• but جاهزان (dual masculine)

The ending -ان is the normal dual nominative ending.

Here, جاهزان is the predicate of a nominal sentence, so it is in the nominative case. That is why you get:

• جاهزان = nominative dual

If the same word were in the accusative or genitive dual, it would normally be:

• جاهزين

So the ending is showing both:

• dual number
• nominative case

Because الثنائية is an adjective describing المصادقة.

Arabic adjectives agree with the noun they describe in:

• gender
• number
• definiteness
• case

So since المصادقة is:

• feminine
• singular
• definite

the adjective must match it:

• الثنائية = feminine singular definite

The fact that both words have الـ shows that this is a noun + adjective phrase, not an iḍāfa.

Because قفل البصمة is an iḍāfa (construct phrase).

In an iḍāfa:

• the first noun usually does not take الـ
• the second noun can make the whole phrase definite

So:

• قفل = lock
• البصمة = the fingerprint

Together:

• قفل البصمة = fingerprint lock

Literally, it is something like the lock of the fingerprint, but in natural English we say fingerprint lock.

A few clues show that it is an iḍāfa:

• The first word قفل has no الـ
• The second word البصمة is a noun, not an adjective
• The meaning is a possession/association structure: lock of fingerprint

If it were a noun + adjective phrase, the adjective would have to match the noun in definiteness and other features. That is not what is happening here.

So:

• المصادقة الثنائية = noun + adjective
• قفل البصمة = iḍāfa

Because of the difference between sun letters and moon letters.

• ث is a sun letter, so the ل in الـ is not pronounced separately. It assimilates into the next sound.
• ب is a moon letter, so the ل is pronounced normally.

So:

• الثنائية is pronounced roughly like ath-th...
• البصمة is pronounced al-ba...

The spelling stays the same, but the pronunciation changes.

It is a noun, specifically a verbal noun (masdar), used here as the standard technical term for authentication.

Arabic often uses verbal nouns in places where English uses abstract nouns like:

• authentication
• verification
• registration
• protection

So in this sentence, it is best to learn المصادقة simply as the normal MSA tech word for authentication.

Not always. The basic meaning of جاهز is ready or prepared, but in technical or interface language it can also suggest things like:

• set up
• available
• enabled
• good to go

So depending on the app or device context, جاهزان could sound like:

• are ready
• are set up
• are enabled

Even though the Arabic word itself is the same.

Because ordinary Arabic writing usually leaves out most short vowel endings.

However, the dual ending is written with actual letters, so you can still see it in normal text:

• -ان
• -ين

That is why جاهزان visibly shows its grammar more clearly than many other words in the sentence.

In fully vocalized Arabic, the other words would also show case endings, but in everyday printed Arabic those short vowels are usually omitted.