Clearly this isn't the dialect I'm accustomed to. I would've said "dù" rather than "ô".
Southern people say dù, Northern people say ô X-D
in other words, different dialects
I write "This is umbrella
Why is this or that not allowed, in english, we use this or that about the same way and it makes full sense ! Why getting this or that wrong... It does not make sense in english, we use this or that the same way... Same value for this or that...
Why isn't a umbrella allowed ?
Đây is usually translated into "here", like in front of you.
Here actually mean "ở đây". "Đây" is something you hold in your hand or something you point at. In this case you point at the umbrella and you said " đây là cái ô"