"This wall is very old."

Translation: Bu duvar çok eski.

[Alaaddin123]

can I say bu duvarı çok eski in order to specify wich wall I am talking about

[AlexinNotTurkey]

Nope, subjects of sentences NEVER take the accusative case :)

[AGreatUserName]

This is a common error here. Check out my answer here:

https://www.duolingo.com/comment/9662697

Also ... bu is already specifying which wall you are talking about.

[MustafaRadwan]

I have a question which is off topic. What is the difference between ESKİ and YAŞLI????

[BrunnoHC]

The latter is usually used with people or animals, otherwise you use the former

[DejaBulluc]

Eski is used for inanimate objects/things
Yaşli is used for people
They both mean old

[RyuYan]

"an old friend" is ambiguous in English.

If I refer to a friend who I have known for a long time , can I say "O eski bir arkadaşım"?

[Sergej611922]

The wall here in Cologne - yes, really very old :)

[allhailthecringe]

May I say "bu duvar çok eskidir"?