What is wrong with "Bu bavulum değil"?
I just kind of sounds wrong :D The issue in question here is that you are stressing that it isn't MY suitcase. In this case, since you are stress the ownership of the suitcase (or lack thereof), it can't really be dropped.
Adding to this;
Benim can only be omitted in a context like:
"Bu, bavulum değil; çantam." (This is not my luggage, it's my bag.)
I was thinking of a context like "This one here is not my suitcase, that one over there is!" - and also put "Bu, bavulum değil"
Can we say "Bu benim bavul değilim" ?
No. Bavul değilim : I am not a suitcase
Not exactly though, it would be “bavulu değilim” ;), That said, it still made me laugh.
Can we say Bu bavul değilim?
:D yes. And that would mean: I'm not this suitcase! I'm actually that luggage over there.
Bu benim valizim değil de ayni şey neden kabul etmiyor????
Valizim should be accepted, shouldn't it?
I wrote "Bu benim bavulum degildir" and this wasn't accepted. Please, can someone explain why
Dinara, it is not accepted because it is about "my suitcase" not "all suitcase, any suitcase of any people in the world". It is not a general statement but a particular/private situation.