السفينة كبيرة.

الـ is the Arabic definite article, the equivalent of the in English.

• سفينة = a ship / ship
• السفينة = the ship

Unlike English, Arabic uses the same definite article for masculine and feminine nouns.

In Arabic, simple present-tense sentences often do not use a separate word for is / am / are.

So:

• السفينة كبيرة literally looks like the ship big
• but it means the ship is big

This is completely normal. In Egyptian Arabic, you usually just put the subject first and then the description.

Because سفينة is a feminine noun, and adjectives must agree with the noun they describe.

So:

• كبير = big for a masculine singular noun
• كبيرة = big for a feminine singular noun

Since السفينة is feminine, the correct form is كبيرة.

Great question. Here كبيرة is not just an adjective inside a noun phrase; it is the predicate of the sentence.

So:

• السفينة كبيرة = The ship is big
• السفينة الكبيرة = the big ship

In السفينة كبيرة, كبيرة is telling you something about the ship, so it stays without الـ.

In السفينة الكبيرة, both words are part of one noun phrase, so both are definite.

They look similar, but they mean different things:

• السفينة كبيرة = The ship is big
  This is a full sentence.

• السفينة الكبيرة = the big ship
  This is just a noun phrase, not a complete sentence by itself.

This is one of the most important differences for learners to notice.

In normal Egyptian pronunciation, final ة is usually pronounced like -a.

So:

• السفينة → roughly safīna / sefīna
• كبيرة → roughly kbīra / kebīra

For an English speaker, the important point is: don’t pronounce the final ة as a strong t in this sentence.

A common Egyptian-style pronunciation would be roughly:

es-safīna kbīra
or
es-sefīna kbīra

Two useful notes:

• In السفينة, the ل of الـ is not clearly pronounced because س is a sun letter, so السـ sounds more like es- or is-.
• كبيرة in Egyptian is often pronounced kbīra rather than a very careful kabīra.

Not as the normal neutral word order.

The usual everyday order is:

• السفينة كبيرة

That is the natural way to say The ship is big.

Starting with كبيرة can sound literary, poetic, or strongly emphatic, but it is not the basic pattern learners should use first.

You would usually say:

السفينة مش كبيرة = The ship isn’t big

In Egyptian Arabic, مش is the normal way to negate this kind of present-tense sentence.

The spelling works perfectly well in Standard Arabic, and Egyptians would also understand it easily.

For an Egyptian learner, the main difference is usually in pronunciation, not in the written form:

• written: السفينة كبيرة
• spoken Egyptian: roughly es-safīna kbīra

So yes, it is fine and understandable for Egyptian Arabic, especially as a simple beginner sentence.