אני אוהבת את הסופרת הזאת, כי כל ספר שלה מעניין.

Because the speaker is female. In the present tense, Hebrew uses forms that show gender, even with אני.

• אני אוהבת = said by a woman
• אני אוהב = said by a man

So the sentence is being spoken by a female speaker.

את is the marker of a definite direct object. It usually does not get translated into English.

Here, the direct object is הסופרת הזאת (this writer / this female author), and it is definite, so Hebrew uses את before it:

• אני אוהבת את הסופרת הזאת

You use את before definite nouns, names, and noun phrases with the, this, that, etc.

In Hebrew, this/that usually comes after the noun:

• הסופרת הזאת = this writer
• הספר הזה = this book

Also, the noun itself takes the definite article ה־:

• סופרת = a female writer
• הסופרת הזאת = this female writer

So the normal order is noun + demonstrative.

סופרת is the feminine form of סופר.

• סופר = male writer / author
• סופרת = female writer / author

So the sentence is talking about a female author.

הזאת means this and agrees with סופרת, which is feminine singular.

Hebrew demonstratives agree with the noun in gender and number:

• masculine singular: הזה
• feminine singular: הזאת

Since סופרת is feminine singular, you get הסופרת הזאת.

Because כל + singular noun often means every or each.

So:

• כל ספר שלה מעניין = every book of hers is interesting

If you say:

• כל הספרים שלה מעניינים

that means all her books are interesting

Both are correct, but they are slightly different:

• כל ספר שלה = every single book of hers
• כל הספרים שלה = all her books as a group

שלה means hers / of her.

Hebrew often expresses possession with של plus a pronoun ending:

• שלי = mine
• שלך = yours
• שלו = his
• שלה = hers

So ספר שלה literally means a book of hers, and in natural English it is often just her book.

Because it matches ספר, which is a masculine singular noun.

• ספר = masculine singular
• מעניין = masculine singular form of interesting

So:

• כל ספר שלה מעניין

If the noun were feminine singular, the form would change:

• כל יצירה שלה מעניינת = every work of hers is interesting

Because Hebrew usually leaves out the verb to be in the present tense.

So Hebrew says, literally:

• כל ספר שלה מעניין = every book of hers interesting

But in natural English, you translate it with is:

• Every book of hers is interesting

This is completely normal in Hebrew.

כי means because.

It connects the two parts of the sentence:

• אני אוהבת את הסופרת הזאת = I like/love this writer
• כי כל ספר שלה מעניין = because every book of hers is interesting

So כי introduces the reason.

Yes. הזו is a very common alternative to הזאת in modern Hebrew.

So both are possible:

• הסופרת הזאת
• הסופרת הזו

They both mean this female writer. Learners will hear both, though הזאת is often presented as the fuller standard form.

Not necessarily. אוהב / אוהבת can mean love or like, depending on context.

In a sentence about an author, it often sounds natural in English as:

• I like this writer
• or I love this writer

The Hebrew form itself can cover either meaning, depending on tone and context.