merhaba,

I meet some problems Plz help me.Thanks.

1.Mecid Türkçe öğrenmek için Türkiyeye geliyor.

2.Mecidin  Türkçe öğrenmesi için Türkiyeye geliyor.

Both sentences are they  right?

If it is wrong ,plz tell me the reason......

Teşekküler!

First sentence is correct and it means 

Mecid Türkçe öğrenmek için Türkiye´ye geliyor.

Mecid is coming to Turkey in order to learn Turkish.

The second sentence is nonsense, unless you add possesive on the main sentence [second part of sentence] 

Mecid´in Türkçe öğrenmesi için Türkiye´ye gelmesi lazım.

Subordinate sentence                  Main sentence

note : main sentence is actually conveys main action which is "Mecid´s coming to Turkey is [being] necessary"  Because The subordinate sentence has POSSESSIVE  [-mesi için] the main sentence should fit to it with POSSESIVE [ -mesi lazım ]

So, the sentence can be translated as [Literally] --> Mecid´s coming to Turkey is necessary for his learning Turkish , which actually can be translated as ---> Mecid should come to Turkey in order to learn Turkish.

Thank you so much, Tunci!

But if "Mecidin  Türkçe öğrenmesi için Türkiyeye götürüyorum."

                         (possessive) 

Mecidin  Türkçe öğrenmesi için Türkiyeye götürüyorum.

subordinate sentence                       main sentence

Main sentence the subject is ben and subordinate sentence the subject is Mecid.

 Is it right?And how to understand this sentence?

2nd sentence seems OK to me. It may not be so meaningful but not gramatically incorrect either.

A translation would be

He´s coming to Turkey for Mecid to learn Turkish. (His coming to Turkey helps Mecid learn Turkish (somehow?))