Saat onu on sekiz geçiyor.  Its 10.18.

Please correct Thank youuu

I think it´s correct but onsekiz is written as one word. 

Just a learner, but I agree with sonunda. See also here:

http://www.turkishclass.com/turkish_lesson_47

 Agree

But Turks also use the 24 hour clock, so you could also say:

Saat on onsekiz´dir.

(It´s 10:18). The longer sentence is it is eighteen minutes past ten