In Turkish grammar, two vowels generally do not follow one another directly. While exceptions exist in foreign loanwords (e.g., Saat, Fiil) or compound words (e.g., Kocaeli), native Turkish suffixes require a "buffer letter" to separate two adjacent vowels.
The Four Buffer Letters: Y, S, Ş, N
To make them easy to remember, Turkish students use the mnemonic word "Yaşasın" (which means "Long live!"). The consonants in this word are the four buffers you will use.
Usage and Examples
Each buffer letter has specific grammatical roles which you will encounter as you progress in your studies. Here is a breakdown of the examples provided:
Word + Suffix | Result | Buffer Letter | Context |
Pencere + in | Pencerenin | N | Genitive Case (Window's) |
Kapı + ın | Kapının | N | Genitive Case (Door's) |
Bahçe + i | Bahçesi | S | 3rd Person Possessive (His/Her garden) |
Araba + ı | Arabası | S | 3rd Person Possessive (His/Her car) |
İki + er | İkişer | Ş | Distributive Numbers (Two each) |
Elli + er | Ellişer | Ş | Distributive Numbers (Fifty each) |
Ütü + e | Ütüye | Y | Dative Case (To the iron) |
Komşu + a | Komşuya | Y | Dative Case (To the neighbor) |
Special Rule for Verbs
If a verb ends in a vowel and is followed by a suffix starting with a vowel (like the future tense), the buffer letter "Y" is almost always used.
Example: İste (to want) + ecek (future suffix) = İsteyecek (He/She will want).