الكلمة دي غلط، والكلمة التانية هي الصح.

Because الكلمة is grammatically feminine in Arabic. In Egyptian Arabic:

• ده = this for masculine singular nouns
• دي = this for feminine singular nouns

So:

• الكتاب ده = this book
• الكلمة دي = this word

A lot of nouns ending in ـة are feminine, and كلمة is one of them.

In Egyptian Arabic, demonstratives like ده and دي usually come after the noun, not before it.

So English says:

• this word

But Egyptian Arabic says:

• الكلمة دي
• literally: the word this

That word order is normal and very common in speech.

Here التانية means the other one or the second one.

In everyday Egyptian Arabic, التاني / التانية can mean either:

• second
• other

The context decides which meaning is intended. In this sentence, since two words are being compared, الكلمة التانية is naturally understood as the other word.

Because it describes الكلمة, and الكلمة is feminine.

Adjectives and similar words often agree with the noun in gender, so:

• التاني = masculine
• التانية = feminine

Since word here is كلمة and that noun is feminine, the sentence uses التانية.

Yes, هي is literally the feminine pronoun that can mean she or it for a feminine noun. But here it is not really being used in the English sense of she.

In Egyptian Arabic, a pronoun like هو or هي can be used in a sentence like this as a kind of linker or emphasis:

• الكلمة التانية هي الصح

It helps give the sense of:

• the other word is the correct one
• or more emphatically, the other word is the right one

So you should not think of it as referring to an actual female person. It agrees with الكلمة, which is grammatically feminine.

Because غلط is the normal word for saying that something like a word, answer, number, or sentence is wrong/incorrect.

So you commonly hear:

• الإجابة غلط = the answer is wrong
• الكلمة دي غلط = this word is wrong

By contrast, غلطان / غلطانة is more often used for a person being mistaken or at fault:

• إنت غلطان = you are mistaken / you are wrong

So for a word, غلط is the natural choice.

Because the two words are behaving a little differently here.

• غلط in الكلمة دي غلط is a predicate adjective: this word is wrong
• الصح in هي الصح is more like the correct one / the right one

So:

• غلط = wrong
• الصح = the correct one

This kind of contrast is very natural in Egyptian Arabic. You are not just saying the second word is correct in a general sense; you are identifying it as the right one.

Not exactly. In التانية, the الـ assimilates to the ت, because ت is a sun letter.

So التانية is pronounced roughly:

• et-tanya

not:

• el-tanya

This is a very common pattern with the definite article in Arabic.

The الـ also assimilates here, because ص is a sun letter too.

So الصح is pronounced roughly:

• eṣ-ṣaḥ
• or more simply for learners, es-saḥ

not:

• el-saḥ

Also, the final ح is the strong Arabic ḥ sound, not the English h exactly.

Yes. Both are natural, but they are slightly different in feel:

• الكلمة دي غلط = this word is wrong
• الكلمة دي مش صح = this word is not correct

غلط is a bit more direct. مش صح is a softer way to say basically the same thing.

Not always. The full sentence is clear and natural:

• الكلمة دي غلط، والكلمة التانية هي الصح.

But if the context is already clear, speakers may shorten it, for example:

• الكلمة دي غلط، والتانية هي الصح.

That means:

• This word is wrong, and the other one is the right one.

Repeating الكلمة just makes the sentence extra clear.