KEYBOARD PROBLEM

Go to Apple Menu / System Preferences / Langauge and Text. Then click on Input Sources, and select the input methods you want to use.

This screen shot is from OS 10.6.8, since I do not know what you have. 10.7 and 10.8 are a little different, but the idea is the same.

Same thing, but this time click on Keyboard and Character Viewer.

Your Menu bar will have a new icon, just to the left of the Speaker icon. Click there.

Click on Show Keyboard Viewer. This will show the specific kb layout the computer is using.

I suggest you experiment with the Language Selection, and see how the keyboard layout changes.

Of course that is not what you want. I suggest you try different languages (in Input Sources), and check the keyboard in each case. Trial and error.

There is another route to try if this does not work out: you may need to trash a Preferences file. Tell me the OS and I can tell you what you have to trash. Please tell us what OS you are running, is it 10.7 or 10.8?

This is very strange.

1. Try changing the Input Source to something other than Turkish? Try U.S, for example, and see what happens.

Also,

2. go to your main drive / Library / Preferences. Is there a file with a name like: com.apple.keyboard.plist

If you find anything with keyboard, just move it to the desktop and see if there is any difference in your keyboard behaviour.

help me wrote:

I clicked show keyboard viewer and when I click "h" it shows this.

It shows your option/alt key is active. I think your keyboard could be damaged so it needs repair or replacement. Try using an external wireless or usb keyboard to test this.

Good call, Tom.

Do you have another kb you could try, following Tom's diagnosis?

help me wrote:

Thanks so much but I have not keyboard for mac

Any usb or wireless keyboard should work.

Is the picture of Keyboard Viewer you posted earlier which shows ^ where h should be no longer correct?

You need a USB keyboard, does not have to be Apple, so long as it connects via USB. Could you take your Macbook with you to a computer store and ask if you can test one of their USB keyboards?