-mekle

Verb stem +  mekle [makla]

This gerund of cause.

Buraya gelmekle    bizi çok mutlu ettiniz.

Cause                    Result of the action

You made us very happy by coming here.

[Your coming here caused us being happy ]

Bunu yapmakla    eline ne geçecek ? 

Cause                 Asking for possible result

What will you gain by doing this ?

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* Negative:

Bu evi satmamakla    yanlış yapıyorsun.

 Cause                     The result that is caused by him not selling this house

You are doing wrong by not selling this house.