זאת עובדה שהוא תמיד מגיע בזמן, אבל אני לא יודעת אם זה רלוונטי לשיחה הזאת.

Because עובדה is a feminine noun, and זאת is the feminine form of this/that when used on its own.

• זאת עובדה = That/This is a fact
• זה ספר = This/That is a book (masculine noun)

In modern Hebrew, זאת and זו are both common feminine forms here.

Literally, it means That is a fact or This is a fact.

Hebrew often uses a very direct structure:

• זאת = this/that
• עובדה = fact

So the sentence begins by stating something firmly: It’s a fact that...

שהוא is made of two parts:

• ש־ = that
• הוא = he

So שהוא תמיד מגיע בזמן means that he always arrives on time.

This is a very common Hebrew structure:

• אני יודע שהוא כאן = I know that he is here
• ברור שהיא צודקת = It’s clear that she is right

In Hebrew, the word ש־ (that) is often written as a prefix attached to the following word.

So instead of writing a separate word, Hebrew commonly does this:

• שהוא = that he is
• שאני = that I
• שזה = that it/this is

This is normal and very common in everyday Hebrew.

Because the idea is he arrives on time, not he is on time in a static sense.

• מגיע comes from להגיע = to arrive
• בזמן = on time

So הוא תמיד מגיע בזמן literally means he always arrives on time.

In English, he is always on time and he always arrives on time are very close in meaning, but Hebrew often uses מגיע בזמן for this idea.

בזמן means on time.

It is made of:

• ב־ = in / at / on
• זמן = time

Together, in this expression, it means on time.

Examples:

• אני רוצה להגיע בזמן = I want to arrive on time
• הוא אף פעם לא מגיע בזמן = He never arrives on time

Because יודעת is the feminine singular form, so the speaker is female.

• אני לא יודע = said by a male speaker
• אני לא יודעת = said by a female speaker

Hebrew verbs in the present tense agree with gender in the singular.

Yes, אם can mean if, but it also often means whether.

So here:

• אני לא יודעת אם זה רלוונטי = I don’t know whether it is relevant

English also sometimes uses if this way:

• I don’t know if it’s relevant
• I don’t know whether it’s relevant

So this is a very natural Hebrew use of אם.

Here זה means it / this.

So:

• אם זה רלוונטי = whether it is relevant

Hebrew often uses זה in a broad, general way, much like English it in sentences such as I don’t know if it’s important.

Because רלוונטי agrees with זה, which is treated as masculine singular.

• זה רלוונטי = it is relevant (masculine singular form)
• זו רלוונטית = this is relevant referring to a feminine noun

Since the sentence says אם זה רלוונטי, the adjective stays masculine singular.

לשיחה means to the conversation or for the conversation depending on context.

It is built from:

• ל־ = to / for
• שיחה = conversation

Because שיחה is definite here (the conversation), the ה of הַשיחה combines with the prefix ל־:

• ל + השיחה → לשיחה

This kind of contraction is very common in Hebrew:

• לבית = to the house
• לילד = to the boy

In Hebrew, demonstratives like הזה / הזאת / האלה usually come after the noun.

So:

• השיחה הזאת = this conversation
• הספר הזה = this book
• הילדה הזאת = this girl

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

It may feel redundant from an English perspective, but in Hebrew this is the normal pattern.

To say this conversation, Hebrew usually uses:

• השיחה הזאת

Both parts are expected:

• ה־ marks the noun as definite
• הזאת means this

The same thing happens in:

• הספר הזה = this book
• האנשים האלה = these people

Yes, but they are used differently.

• זאת can stand alone: זאת עובדה = That/This is a fact
• הזאת follows a noun: השיחה הזאת = this conversation

So the difference is mostly grammatical:

• standalone form: זאת
• noun modifier after a feminine noun: הזאת

Because אבל means but, and it joins two full clauses:

• זאת עובדה שהוא תמיד מגיע בזמן
• אבל אני לא יודעת אם זה רלוונטי לשיחה הזאת

Just like in English, a comma before but is very natural here.

Yes, this is very natural Hebrew.

The structure is:

• statement: זאת עובדה...
• contrast: אבל...
• uncertainty/opinion: אני לא יודעת אם...

A Hebrew speaker might also say similar versions, such as:

• זה שהוא תמיד מגיע בזמן זה עובדה, אבל אני לא יודעת אם זה רלוונטי לשיחה הזאת.
• נכון שהוא תמיד מגיע בזמן, אבל אני לא יודעת אם זה רלוונטי לשיחה הזאת.

But the original sentence is completely normal and natural.