هذا الطبق نظيف، لكن هذه الملعقة متسخة.

Because الطبق is a masculine noun, while الملعقة is a feminine noun.

In Modern Standard Arabic, the demonstrative this changes depending on gender:

• هذا = this for masculine nouns
• هذه = this for feminine nouns

So:

• هذا الطبق = this plate
• هذه الملعقة = this spoon

A very common clue for feminine nouns is the ending ـة (taa marbuuTa), as in ملعقة.

Because adjectives in Arabic must agree with the nouns they describe in gender and definiteness.

Here:

• الطبق is masculine, so the adjective is masculine: نظيف
• الملعقة is feminine, so the adjective is feminine: متسخة

So the pattern is:

• masculine: نظيف = clean
• feminine: متسخة = dirty

This is a very important rule in Arabic: adjectives match the noun.

In the present tense, Arabic usually does not use a separate word for is / are in sentences like this.

So:

• هذا الطبق نظيف literally looks like this plate clean
• but it means this plate is clean

And:

• هذه الملعقة متسخة = this spoon is dirty

This kind of sentence is called a nominal sentence in Arabic.

If you wanted to say was, then Arabic would use a verb such as كان.

In Arabic, adjectives normally come after the noun they describe.

So:

• الطبق النظيف = the clean plate
• الملعقة المتسخة = the dirty spoon

In your sentence, the same rule is happening, just in a predicate structure:

• هذا الطبق نظيف
• هذه الملعقة متسخة

English usually puts many adjectives before the noun, but Arabic usually puts them after.

لكن means but.

It connects two contrasting ideas:

• هذا الطبق نظيف = this plate is clean
• لكن = but
• هذه الملعقة متسخة = this spoon is dirty

So it works very much like English but.

In careful grammar, you may also see لكنَّ with different usage in some contexts, but here لكن is the simple conjunction but.

الـ is the Arabic definite article, meaning the.

So:

• طبق = a plate / plate
• الطبق = the plate

and:

• ملعقة = a spoon / spoon
• الملعقة = the spoon

In this sentence, both nouns are definite:

• هذا الطبق = this plate
• هذه الملعقة = this spoon

Demonstratives like this often go with definite nouns in Arabic.

The ending ـة is called taa marbuuTa. It very often marks a word as feminine.

Examples here:

• ملعقة = spoon, feminine noun
• متسخة = dirty, feminine adjective

This helps show agreement:

• feminine noun → feminine adjective

But remember: ـة is a strong clue, not an absolute rule for every single word in Arabic.

A simple pronunciation guide is:

• هذا الطبق نظيف، لكن هذه الملعقة متسخة
• hādhā aṭ-ṭabaqu naẓīfun, lākin hādhihi al-mil‘aqatu muttasiḫatun

A few helpful notes:

• هذا is pronounced roughly haa-dhaa
• هذه is pronounced haa-dhi-hi
• الطبق is often heard as aṭ-ṭabaq, because the l in al- assimilates before ط
• نظيف has an emphatic ẓ sound
• متسخة has the kh sound, like the ch in Scottish loch

In normal reading and speech, many final case vowels are not pronounced.

Because ط is a sun letter.

When الـ comes before a sun letter, the l sound of al- is absorbed into the next consonant. So:

• written: الطبق
• pronounced: aṭ-ṭabaq

This happens with many letters, such as ت، د، ر، س، ش، ص، ض، ط، ظ، ل، ن

By contrast, with moon letters, the l is pronounced clearly.

Yes. In fully vocalized formal Arabic, it can be read as:

• هٰذَا الطَّبَقُ نَظِيفٌ، لَكِنْ هٰذِهِ الْمِلْعَقَةُ مُتَّسِخَةٌ

With case endings, the subjects and predicates here typically end in -u / -un in citation-style reading.

However, in everyday reading, news reading, and most unvocalized text, learners usually do not pronounce every final case ending consistently.

So it is completely normal at an early stage to focus first on the main words and agreement patterns.

Because هذا agrees with the gender of the noun, not with whether the noun has الـ.

So:

• هذا طبق = this is a plate / this plate
• هذا الطبق = this plate

And:

• هذه ملعقة
• هذه الملعقة

The presence of الـ does not change the gender, so هذا stays masculine with الطبق, and هذه stays feminine with الملعقة.

In Modern Standard Arabic, the most standard form is:

• هذا الطبق
• هذه الملعقة

You may encounter structures like الطبق هذا in some dialects or less formal usage, but for MSA, learners should stick with:

• demonstrative + noun

So for formal Arabic, هذا الطبق and هذه الملعقة are the safest choices.

It is an adjective, but it is built differently.

• نظيف is a basic adjective meaning clean
• متسخ / متسخة is also an adjective meaning dirty

So here you have:

• masculine: متسخ
• feminine: متسخة

Even though the two adjectives have different shapes, they behave the same way grammatically: they agree with the noun in gender and come after the noun they describe or serve as the predicate after it.