hello all teachers,
i have such guestion.. there is sentence - Bu kalemdir. and sentence- Bu kalem. what is the difference? when we have to use that "dir" on the end of noun. is that the same as in english "THE" ? thank you in advance.

Ihey are identical for all practical purposes/

BU KALEMDIR carries morr conviction

I will try too

Bu kalem = This pen.

Bu kalemdir = This is pen.

Bu bir kalemdir = This is a pen.
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Bu, kalemdir = This is pen.

Aradığımız bu kalemdir. = The thing that we look for is that pencil.

But sometimes------------------------------------------------

Aldığım yalnızca bir çiçek.
Aldığım yalnızca bir çiçektir.

Here both sentences means "The thing that i bought is just a flower."

Here second sentence is more stressed.
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the (-dir ,-dır . -tir , -tır) are used like an informative statement
ex.
This is a book. Bu bir kitaptır
That’s a chair. O bir sandalyedir.
What’s that? O nedir?

tessekur ederim. anladim.