which one is correct? to reach someone
what is the best number to reach you on?
what is the best number to reach you?
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which one is currect? I wonder why they add an "on" here?Thank you!

Question

Answer

It's the second one. You usually don't end sentences with a preposition.

"What is the best number to reach you?"

Answer

Thank you Wendy. However, I also know the rule that you should omit the proposition at the end of setences. In this case, can I omit "on"?

Answer

Thank you Su.Ki. However, I also know the rule that you should omit the proposition at the end of setences. In this case, can I omit "on"?

Answer

You can also say "What is the best number to reach you at?"

Answer

The first is correct, because you reach somebody ON a number. For example, "You can reach me on 77643" or "77643 is the best number to reach me on". It  would be wrong to omit the 'on'.