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It is not really necessary. 

In Turkish grammar we have term for that type of situation which is Incoherency.  I had written about it some time ago. And in your case, the incoherency is caused by unnecessaryly used word.

 Incoherency caused by unnecessaryly used words.

Duvarlara kalemle yazı yazmayınız. [ Do not write on the walls with pen]

Here, the incoherency is caused by using the unnecessary word "kalem"  since it is a warning and we are just asked " do not write on the walls"  it doesn´t matter what tool we use when we write on the walls.

Therefore, that warning should be as ; 
Duvarlara yazı yazmayınız.

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İki bakan, üç saat süreyle görüştüler. [ Two ministers talked for 3 hours time]

Again, the word ´süreyle´ is unnecessary and causes incoherency.

So, the sentence should be as ;

İki bakan, üç saat görüştüler.

Another example  ;

After the particle "ile" , the word "birlikte" should not be used as they both give almost the same meaning.

ile = with 

birlikte = together 

So, its unnecessary to use "birlikte" after "ile"

Buraya kardeşiyle  birlikte geldi --> He/She came here together with his brother/sister.  

In the sentence above, we should get rid of "birlikte" [together] , as there is already "with"  "kardeşi + ile = kardeşiyle ´