אם אני לא שומעת אותך בטלפון, תדבר לאט יותר.

Because the speaker is female.

In the present tense, Hebrew verbs agree with the subject in gender and number. So:

• אני שומעת = a woman saying I hear / I can hear
• אני שומע = a man saying I hear / I can hear

So this sentence is being said by a woman.

Because the person being addressed is male.

Hebrew often marks gender in the you forms of verbs. Here:

• תדבר = you should speak / speak to one male
• תדברי = the same thing to one female

So this sentence, as written, is from a female speaker to a male listener.

If the listener were female, it would be:

אם אני לא שומעת אותך בטלפון, תדברי לאט יותר.

אותך means you as a direct object.

In this sentence, the speaker is hearing you, so Hebrew uses the object form:

• שומעת אותך = hear you

But אתה means you as the subject of a sentence:

• אתה מדבר = you are speaking

So:

• אתה = subject you
• אותך = object you

Without vowel marks, אותך can represent two different pronunciations:

• אותך = otkha when speaking to a male
• אותך = otakh when speaking to a female

The spelling is usually the same in normal Hebrew writing, so you figure it out from context.

Here, because the next verb is תדבר, which is masculine, אותך should be understood as otkha.

בטלפון means on the phone or over the phone.

It is made of:

• ב־ = a preposition that can mean in, on, at, by, through, depending on context
• טלפון = telephone / phone

So even though English says on the phone, Hebrew uses ב־ here. That is very normal.

Because in modern Hebrew, the future 2nd-person form is very often used to give instructions, requests, or commands.

So both of these can work:

• תדבר לאט יותר = speak more slowly
• דבר לאט יותר = imperative speak more slowly

But תדבר is extremely common in everyday speech and can sound a little more natural or a little less abrupt.

In this context, it usually means I can’t hear.

Hebrew often uses the simple verb where English would use can or be able to. So:

• אני לא שומעת אותך can naturally mean I don’t hear you or I can’t hear you

Here, because it is about the phone and asking someone to speak more slowly, the intended meaning is clearly I can’t hear you.

A more explicit version would be:

אם אני לא יכולה לשמוע אותך בטלפון...

But that sounds heavier and less natural in this kind of everyday sentence.

Yes, it could be future in some contexts, but the present tense here sounds more immediate and natural.

• אם אני לא שומעת אותך בטלפון = if I’m not hearing you / if I can’t hear you on the phone
• אם לא אשמע אותך בטלפון = if I don’t hear you on the phone in a more future or hypothetical sense

The sentence you have feels like a real, current situation: the conversation is happening now, and the speaker is reacting to it.

לאט means slowly, and יותר means more.

So:

• לאט יותר = more slowly

This is a common way to make comparisons in Hebrew:

• מהר יותר = faster
• חזק יותר = louder / stronger
• ברור יותר = more clearly / clearer, depending on context

You may also hear יותר לאט in speech. Both word orders are used, but לאט יותר is very natural here.

Yes. The sentence combines information about two different people:

• אני לא שומעת tells you about the speaker: female
• תדבר tells you about the listener: male

So the full sentence is specifically:

• said by a woman
• said to a man

That kind of mixed gender marking is very common in Hebrew, and it is one of the things English speakers often need to get used to.