# Dictionary of Spoken Russian/Russian-English/Section 4

§4. ALTERNATIONS OF SOUND AND SPELLING
In this Section we describe alternations of sound which are shown in Russian writing and accordingly bring it about that some forms of words are spelled in ways that differ from the related forms.
1. Change of [g, k, x]. Within a word, when the sounds [g, k, x] come to stand before the vowels [e, i], they are replaced by their soft varieties [gj, kj, xj]. The writing shows this by using the letters е, и for the vowels. Thus, with вор [vor] "thief," воры [vori] "thieves" compare the following: знак [znak] "sign," знаки [znakji] "signs"; плуг [pluk] "plow," плуги [plugji] "plows"; успех [uspjex] "success," успехи [uspjexji] "successes."
2. Insertion of Vowels. When the last consonant of a cluster is [c, g, k, l, lj, n, nj, r, rj, s, sj, y] and comes to stand at the end of a word or before the consonant of a suffix, a vowel is inserted. Thus we have ковры [kavri] "rugs," with the ending [-i], but ковёр [kavjor] "rug," with no ending and an inserted vowel. The choice of the inserted vowel is made as follows:
If either of the two last consonants in the cluster is [g, k, x], the inserted vowel is [o]:
куски [kuskji] "pieces": кусок [kusok] "piece" когти [koxtji] "claws": коготь [kog'tj] "claw" коньки [kanjkji] "skates": конёк [kanjok] "skate"
Otherwise, if the last consonant is [c] or [y], the inserted vowel is [je]; the [j] means that the preceding consonant is made soft if possible:
отцы [atci] "fathers": отец [atjec] "father" перцу [pjercu] "some pepper": перец [pjerj'c] "pepper" ручьи [ručyi] "brooks": ручей [ručey] "brook" ульи [uljyi] "beehives": улей [ulj'y] "beehive"
In all other cases the inserted vowel is [jo]; that is, [o] with softening of the preceding consonant were possible:
котлы [katli] "kettles": котёл [katjol] "kettle" пепла [pjepla] "of ashes": пепел [pjepj'l] "ashes" смешно [smjišno] "it's funny": смешон [smjišon] "he's funny" страшно [strašna] "it's terrible": страшен [straš'n] "he's terrible"
​There are quite a few irregularities. Thus, beside во сне [va snje] "in one's sleep," there is сон [son] "sleep," with [o] inserted instead of [jo]. Some words, like блеск [bljesk] "sheen," do not insert a vowel. These irregularities are shown in the dictionary.
Words ending in consonants other than those named do not insert vowels: мост [most] "bridge," чувств [čustf] "of feelings."
3. Spelling of Prefixes. When a prefix ending in a hard consonant combines with a form that begins with [i], this vowel, in accordance with the general habit, gets the dull sound, and this is shown in the spelling: играть [igratj] "to play" with prefix c- gives сыграть [sigratj] "to play off." In the case of prepositions, which are written (but not pronounced) as separate words, the same habit obtains, but the writing does not show it: игра [igra] "game," с игрой [s igroy] "with the game": [i] here has its dull sound.
When a prefix ending in a hard consonant comes before a form with initial [y], the letter ъ is added, indicating a hard consonant before [y]: есть [yestj] "to eat" with prefix с- gives съесть [syestj] "to eat up."
Prefixes ending with [z] are written with с before unvoiced mutes (§3).