Can I say 'the' twice when I use 'of' ?

Hi, I was always curious about this grammar.

Can you tell me if these sentences are correct?

#1. I will let you know the schedule of the product.
#2. I will let you know the schedule of product.
#3. I will let you know schedule of the product.
#4. I will let you know schedule of product.

#5. I will let you know the ETS of the sample.
#6. I will let you know the ETS of sample.
#7. I will let you know ETS of the sample.
#8. I will let you know ETS of sample.

Thank you for reading this.

Question

Can I say 'the' twice when I use 'of' ?

Hi, I was always curious about this grammar.

Can you tell me if these sentences are correct?

#1. I will let you know the schedule of the product.
#2. I will let you know the schedule of product.
#3. I will let you know schedule of the product.
#4. I will let you know schedule of product.

#5. I will let you know the ETS of the sample.
#6. I will let you know the ETS of sample.
#7. I will let you know ETS of the sample.
#8. I will let you know ETS of sample.

Thank you for reading this.

Answer

There is nothing wrong with saying "the" twice.  In general, it is good (but not necessary) to avoid using the same word twice in a sentence. However, for this purpose I would not count "the" as a word.

None of these eight sentences is wrong. A context could be invented for each one but #1 and #5 are the safest. It would take some skill to invent contexts for #2, 3, 4, 6, 7, or 8, but it is possible.

Answer

It’s okay to use “the” twice. But it doesn’t sound as free-flowing and consistent. What you could do is switch the position and add “ ‘s “.

Example:

I will let you know the product’s schedule.

I will let you know the product’s ETS.

Hope this helped!