التليفون ده سريع، بس الكمبيوتر بطيء.

In Egyptian Arabic, the present-tense verb to be is usually not said.

So:

• التليفون ده سريع = This phone is fast
• literally, it looks more like the-phone this fast

This is very normal in both Egyptian Arabic and Standard Arabic for simple present-tense sentences.

If you want another tense, then you do use a verb, for example:

• التليفون ده كان سريع = This phone was fast
• التليفون ده هيبقى سريع = This phone will be fast

Because in Egyptian Arabic, the common word for this usually comes after the noun:

• التليفون ده = this phone
• الكمبيوتر ده = this computer

That is different from English, where this comes before the noun.

It is also different from Standard Arabic, where you often see:

• هذا التليفون or هذا الهاتف

So in Egyptian, noun + ده/دي is the normal everyday pattern.

Yes, ده means this, but in Egyptian Arabic, demonstrative phrases usually use:

• the noun with الـ
  • ده/دي

So:

• التليفون ده = this phone
• البنت دي = this girl

Even though it looks a bit like the phone this word-for-word, that is simply how Egyptian Arabic normally forms this + noun.

So the الـ here is not extra or wrong. It is part of the usual structure.

Because here they are predicates, not attributive adjectives.

In this sentence:

• التليفون ده سريع = This phone is fast
• الكمبيوتر بطيء = The computer is slow

The words سريع and بطيء are telling you something about the noun, so they do not take الـ here.

Compare:

• التليفون سريع = The phone is fast
• التليفون السريع = the fast phone

That second one is an adjective directly modifying the noun, so it takes الـ too.

So:

• predicate adjective: no الـ
• adjective inside a noun phrase: usually matches definiteness

Here, بس means but:

• التليفون ده سريع، بس الكمبيوتر بطيء = This phone is fast, but the computer is slow

But بس can also mean only / just in other contexts.

For example:

• أنا عايز دقيقة بس = I only want a minute
• بس كده = that's all / that's it

So the exact meaning of بس depends on context. In your sentence, it clearly means but.

A simple pronunciation guide is:

• et-telefōn da sarīʿ, bass el-kombyūter baṭīʾ

A few helpful notes:

• التليفون: the الـ is pronounced more like et- here because ت is a “sun letter,” so the l sound blends into the t
• ده sounds like da
• بس is bass, with a clear s
• بطيء ends with a hamza sound, a small catch in the throat: ba-tee’

You do not have to make it perfect right away. A learner-friendly version like et-telefon da sareeʿ, bas el-kombyuter bateeʾ is fine to start with.

Because ده is the masculine singular form, and تليفون is treated as masculine singular.

So:

• التليفون ده = this phone

For a feminine singular noun, you usually use دي:

• العربية دي سريعة = This car is fast

So the choice depends on the gender of the noun:

• ده = masculine singular
• دي = feminine singular

In Egyptian Arabic, you usually use مش before the adjective or predicate.

For example:

• التليفون ده مش سريع = This phone is not fast
• الكمبيوتر مش بطيء = The computer is not slow

So the full negative version could be:

• التليفون ده مش سريع، بس الكمبيوتر مش بطيء

Even if the English meaning changes, the grammar pattern is the useful part:

• noun + مش + adjective

They are related, but they mean different things.

• التليفون ده سريع = This phone is fast
• ده تليفون سريع = This is a fast phone

In the first sentence:

• التليفون ده is the full noun phrase: this phone
• سريع is the predicate: fast

In the second sentence:

• ده means this
• تليفون سريع means a fast phone

So the structure changes the meaning:

• التليفون ده سريع → talking about a specific phone and describing it
• ده تليفون سريع → identifying something as a fast phone

No. التليفون ده سريع means this phone is fast.

If you want this fast phone, you need the adjective inside the noun phrase:

• التليفون السريع ده = this fast phone

Compare:

• التليفون ده سريع = This phone is fast
• التليفون السريع ده = this fast phone

That is a very important difference in Arabic:

• adjective as part of the noun phrase = the fast phone
• adjective as the predicate = the phone is fast