Hello everyone As you can see I'm new to the forum, and I've only just recently decided to try and learn turkish. I love the fact that everything is spoken as it is written, and most things make more logical sense than english, such as pronouns.

However I am a bit confused about the pronoun for kötü, when saying "I am bad" it's kötüsün, but I would expect it to be kötüsin. Could somebody please tell me why it's like this? Is it just simply irregular for no apparent reason or is it because it's easier to say outloud? Also does this happen much in words?

Thanks and kind regards,
Rob.

Kötüsün = You are bad.
Kötüyüm = I am bad.

The reason it is not -sin-, is because of the vowel-harmony. if you take a look at the grammar-section of this webpage, you will find a few lessons of the vowel-harmony. If I were you I'd really study this thoroughly, as they are the fundaments of many Turkish grammar rules!

In kötüsün: the last vowel of the word kötü is a ü. Therefore, the suffix which is -sin-, changes into sün.

If the last vowel is o » the suffix becomes 'sun'
If the last vowel is ö » the suffix becomes 'sün'
If the last vowel is i » the suffix remains 'sin'
If the last vowel is ı » the suffix becomes 'sın'
If the last vowel is e » the suffix remains 'sin'
If the last vowel is a » the suffix becomes 'sın'.

I'm not sure if I remembered them all correctly, but you should just check out the pages about it.

Some examples:

güzel » last vowel is an e » güzelsin (you are beautiful)
kötü » last vowel is a ü » kötüsün (you are bad)
iyi » last vowel is an i » iyisin (you are good)
akıllı » last vowel is an ı » akıllısın (you are smart)

Very quick reply! I'll go check it out now. Tessekürler

Welcome to TC you'll love it here!!