does this mean it is incorrect to put "hai" in the sentence twice?
You could, but it's often omitted when the statement is negative.
Actually its pretty obvious that he is not eating
It's only actually wrong on a "tap what you hear" question, because it's not in the audio. :-)
Otherwise, it's correct to omit it if you want.
Is है removed in the 1st part of the sentence because the statement is negative or because there is already है at the end of the sentence? Or both?
@ZelieZazou - Because the statement is negative. If the first statement was positive, then you will need to put है after the first statement too. E.g. Raj is eating because he is hungry = राज खाना खा रहा है क्योंकि उसे भूख लगी है
आपके जवाब के लिए धन्यवाद :)
Is it correct to say that native speakers omit the bindi in क्योंकि?
Why no hai after he is not eating?
Since the statement is negative, you can omit the है.
He is not easting as he is sleeping - this means the same but was marked wrong. Why?
Whats wrong in my answer
Does this mean it s incorrect to put hai. In the sentence twice
Not incorrect, but highly unusual; hence sounds unnatural to most native speakers.
"वह नहीं खा रहा क्योंकि सो रहा है।"
Would this be correct too? Duolingo says not, but Duolingo doesn't know it all after all.
No. It won't be correct.
The same way "He is not eating because sleeping" doesn't make sense. The verb 'sleeping' needs a "doer", even in Hindi.