Turkish Vowels - Some rules on words and sounds

All vowels are pronounced short. Vowels never follow each other. To prevent this, buffer letters are inserted in between, these can be y, n, s - but each has it own rules of addition.
All vowels obey the 1st and 2nd rule of vowel harmony.
Most English prepositions - to, from, in ,on, at etc. - becomes suffixes in Turkish (very few can also be used as separate words).

Consonants:

Words never start with a soft-g - ğ - there are no exceptions to this rule.
Words can not end in: b, c, d, g, (there are a few of exceptions). In words of foreign words, these are converted to p, ç, t, k.

Exceptions to all rules above:

(a) Words of foreign origin.
(b) Composite words (two words combined together).

Turkish Vowel Classification

Turkish Vowel Qualities
 StraightRounded
 WideNarrowWideNarrow
Thickaı - (Undotted)ou
Thinei - (Dotted)öü

Vowel Production

(A) According to the position of tongue and exit.
Thick vowels: a, ı, o, u.
Thin vowels: e, i, ö, ü.

(B) According to the lips positioning.
Straight vowels: a, e, ı, i.
Rounded vowels: o, ö, u, ü

(C) According to the mouth opening.
Wide Vowels: a, e, o, ö.
Narrow vowels: ı, i, u, ü

First rule of vowel harmony

This Rule concerns the Vowels A and E

1. The Vowel A must follow the A-Undotted group A I O U
2. The Vowel E must follow the E-Dotted group E İ Ö Ü

Vowels are divided into two groups:
Thick vowels: a, o, u, ı
Thin vowels: e, ö, ü, i
Rule: Normally, a word consists of either thick or thin vowels. And all rules applying to one set of (thick or thin) vowels apply symmetrically also to the other set.

Examples:

Thick Vowels: Konuşacağımızı - that we will speak
Thin Vowels: Görüşeceğimizi - that we will meet/correspond
Some exceptions:
(a) Combined words: denizaltı [deniz + altı] - submarine
(b) Words of foreign origin: otobüs [autobus] contains both thick and thin vowels
(c) The present continuous tense suffix -yor. - is invariable, there is no vowel change to letter O.

The Two Groups of Vowels

The eight thick vowels can be grouped as without dots (a, ı, o, u), and thin vowels as with dots (e, i, ö, ü). This symmetry simplifies the 2nd rule of vowel harmony.

Second rule of vowel harmony

This Rule concerns the Vowels I, İ and U, Ü

There are two different forms of I (İ) and U (Ü) in Turkish - so for Vowel harmony to operate:
1. The Undotted Forms of I or U must follow the A-Undotted group A I O U
2. The Dotted Forms of İ or Ü must follow the E-Dotted group E İ Ö Ü

Vowel Harmony Reference

When adding: -a or -e suffixes
Where Final Vowel is: -a, -ı, -o, -uadd-a
Where Final Vowel is: -e, -i, -ö, -üadd-e
When adding: or -u undotted suffixes
Where Final Vowel is: -a or -ıadd Undotted
Where Final Vowel is: -o or -uadd-u
When adding: -i or dotted suffixes
Where Final Vowel is: -e or -iadd Dotted -i
Where Final Vowel is: -ö or -ü add

Following Vowels

This vowel can only be followed by either of these vowels:
a - is followed by - a, ı
ı - is followed by - a, ı
o - is followed by - a, u
u - is followed by - a, u

And (by the 1st rule of vowel harmony) this vowel can only be followed by either of these vowels:
e - is followed by -e, i
i - is followed by -e, i
ö - is followed by -e, ü
ü - is followed by -e, ü

A subsequent (2nd, 3rd) syllable can only contain an a/u/ı or an e/ü/i.
In the same way, an o or ö can only occur in the first syllable.
with composite words eg: bugün - today = bu (this) + gün (day) - each component word is considered separately for the rules of vowel harmony.