Lesson 5– Assimilation

 This is a topic I forgot to mention in the Lesson 1. Native speakers do it automatically, we don't even realise it.
     What is assimilation? It is a phonological process by which one sound becomes more similar to the previous one or the following one. It is usually done to facilitate pronunciation. When voiced and voiceless sounds meet, one of them turns into a voicless sound.
      First, you need to find out the difference between voiced and voiceless consonants:

D x T  (dry x try)
G x K (gone x calm)
Z x S (zygote x sleep)
H x Ch (hold x loch ness)
B x P (burst x plant)
V x F (via x fake)
Ď x Ť (dy x ty)
Ž x Š (pleasure x mushroom)
N x N (note x fang)
Ř x Ř (tři x dři) => you don't have to pay attention to this one, because it is impossible to pronounce voiced "ř" after any voiceless consonant and vice versa.
(Other consonants don't assimilate.)

Assimilation in the middle/ at the end of words

V x F

borůvka, f. ['boa-roof-kah] (blueberry) – "k" is a voiceless sound, therefore you have to read "v" as "f"

plav ['pluf] (swim!) – it sounds weird when pronouncing each sound voiced, especially those at the end of words, therefore "f" instead of "v"

BUT!

zavolat ['zah-voa-lut] (call) – "o" is a vocal, it doesn't change anything about the pronunciation of the word

B x P

trubka, f. ['troup-kah] (tube) – "k" is a voiceless consonant, "b" is read as "p"

zob, m ['zoap] (seed for poultry) – "b" at the end of a word is pronounced as "p"

BUT!

obvaz, m. ['oab-vus] (bandage) – "v" is a voiced sound, so you must read "b" as "b"

zip, m. ['zip] (zip)

D x T

vodka, f. ['voat-kuh] (vodka) – "d" => "t"

med, m. ['met] (honey) – "d" => "t"

BUT!

medvěd, m. ['med-vyeht] (bear) – "v" is a voiced consonant, therefore the preceding "d" is really read as "d" 

kat, m. ['cut] (executioner)

Ď x Ť

choďte ['choaty-teh] (walk!) – "t" is a voiceless consonant, so "ď" is read as "ť"

káď, f. ['ca:ty] (tub) – "ď" at the end of a word is read as "ť"

BUT!

nať, f. ['nutye] (leaves)

Z x S 

kaz, m. ['cus] (flaw) – "z" => "s"

oblázky, pl., m. ['oab-lu:s-kih] (pebbles) – "k" is a voiceless sound, "z" => "s"

BUT!

jízda, f. ['yie:z-duh] (ride) – "d" is a voiced sound, so "z" must be read as "z"

les, m ['les] (forrest)

Ž x Š

muž, f. ['moush] (man)– "ž" is at the end of the word, so it must be read as "š"

pokožka, f. ['poa-kosh-kuh] (epidermis)  – "ž" => "š"

BUT!

kůže, f. ['coo-sue] (skin) – "e" is a vocal, it doesn't change anything about word's pronunciation

veš, f. ['vesh] (louse)

H x Ch

výtah, m. ['vee-tuch] (lift/ elevator) – "h" => "ch"

nehty, pl. m. ['nech-tih] (nails) – "h" => "ch"
BUT!
nehoda, f. ['neh-hoa-duh] (accident) – "o" is a vocal, it doesn't change anything about the pronunciation
hoch, m. arch. ['hoach] (boy)

You don't have to memorize all of these; as you listen to the words, you'll start doing it subconsciously.

love & peace
Ciray