We all have a mother tongue which functions as a filter for what sounds we are able to distinguish. When you learn a foreign language, you have to understand that it uses a different set of sounds and different orthographic rules than your mother tongue (i.e. the same letter written in a different language may be pronounced differently). What learners often do is that they try to approximate the sounds by the ones they are already familiar with and read words as if they were written in their native languages. Here’s a list of the most common errors of this type:
au in English is pronounced as /ɔː/ (as “aw” in “law”), not as /au/, as in many other languages; for example “auto-” is pronounced /ɔːtə/, as in “autobiography” /ˌɔtəbaɪˈɒgrəfi/ (aw-tə-by-ogg-rə-fee) and “autopsy” /ˈɔːtɒpsi/ (aw-top-see).
ps at the beginning of a word is pronounced just as /s/, such as in “psychology” /saɪˈkɒlədʒi/ (saai-koll-ə-dzhee) or “pseudonym” /ˈsjuːdənɪm/ (syoo-də-nim) (UK), /ˈsuːdənɪm/ (soo-də-nim) (US).
eu unlike perhaps all other languages, “eu” in English is pronounced as /jʊ/ (mostly UK) or /ʊ/ (mostly US), and sometimes also long. Examples include “Euclid” /jʊˈklɪd/ (yu-klid), “pneumatic” /njuːˈmætɪk/ (nyoo-mæ-tik), or “neuron” /ˈnjʊərɒn/ (nyu-ə-ron) (that was the UK variant; US pronunciation of the latter two doesn’t contain /j/).
pn at the beginning of a word is pronounced as /n/, e.g. “pneumatic” (see above), “pneumonia” /njuːˈməʊniə/ (nyoo-moh-nee-ə) (UK), /nuːˈməʊniə/ (noo-moh-nee-ə) (US).
kn at the beginning of a word is pronounced as /n/, e.g. “know” /nəʊ/ (noh), knee /niː/ (nee), knife /naɪf/ (naayf).
x at the beginning of a word is pronounced as /z/, not as /ks/, for example “xenophobia” /ˌzɛnəˈfoʊbiə/ (zen-ə-foh-bee-ə) or “Xena” /ˈziːnə/ (zee-nə) a fictional character).
w is never pronounced as v – many languages don’t have the “w” sound (such as in the word “wow”), and the speakers stubbornly pronounce English w as v (as in “very”). However, the distinction is sometimes crucial to be understood, such as in the words “vest” (a piece of garment) and “west” (one of the cardinal directions). Just remember that to say “w”, you have to make a narrow “slit” with your mouth with lips not touching the teeth.
v is never pronounced as w — those who do realize that English has a sound as in “wow” often use this sound for all English words containing w or v. However, v is never pronounced as in “wow”, but always as in “very”, by making the lower lip touching upper teeth.
ch is often not pronounced as
“ch” – in most languages, the pronunciation rules for the digraph “ch” differ from the English ones. In French it is usually /
ʃ/ (which can still be heard in the English word “chef” /
ʃef/; see also my article that lists all common English words in which
“ch” is pronounced as “sh”), in German it can be /
x/, as in Scottish Loch Ness /
ˌlɒx ˈnes/. In standard English, however, it is virtually always either /
tʃ/ (chat, chalk, chapter) or /
k/ (character, chrome, orchestra), but there’s no reliable rule to decide which one is the correct one, so it has to be remembered. Note: In some British dialects, the pronunciation is sometimes somewhere between /
tʃ/ and /
ʃ/.
e is often not pronounced as /ɛ/ (as in get) – “e” in non-stressed syllables is often pronounced as /ɪ/ (as “i” in “pit”), especially in words beginning with “de-”, such as “detective” /dɪˈtɛktɪv/ (di-tek-tiv), “delay” /dɪˈleɪ/ (di-lei), or “delete” /dɪˈliːt/ (di-leet). However, when “de-” is stressed, it is usually pronounced as /dɛ/, e.g. “decorate” /ˈdɛkəˌreɪt/ (dek-ə-reyt).
th in English is pronounced either as /θ/ or /ð/. The former is pronounced similarly as /t/ and the latter similarly as /d/, but the tongue touches the back side of upper teeth, not just the upper palate (the fleshy part behind the teeth, pronounced /ˈpælət/). They are not pronounced as “s” and “z”! The distinction can be crucial—there was a funny German commercial for a language school, in which a young worker at the German Coast Guard receives a distress call: “Mayday, mayday … Can you hear us … We are sinking!”, to which he replies, with a strong German accent: “Hallo … What are you sinking about?”
Another common problem is the pronunciation of the letter “o”. It is usually pronounced as /əʊ/ (UK) or /oʊ/ (US) in open stressed syllables (e.g. go, vote, hope) or /ɒ/ (UK) and /ɑ/ (US) in closed stressed syllables (e.g. hot, god, pot) (/ɒ/ sounds like “o” in most European languages , /ɑ/ sounds as something between “o” and “a” in “father”).
There is, however, also another, less common pronunciation of “o”, namely /ʌ/. For example the word “come” is pronounced /kʌm/; the /ʌ/ is the same sound as in “but” /bʌt/. Below are the most common ones; if you are not a native speaker, I believe some of them might surprise you. The bold ones are very commonly pronounced wrong.
among /əˈmʌŋ/;
another /əˈnʌðə/ (UK), /əˈnʌðər/ (US);
brother /ˈbrʌðə/ (UK), /ˈbrʌðər/ (US);
colour /ˈkʌlə/ (UK), color /ˈkʌlər/ (US);
come /kʌm/;
comfortable /ˈkʌmfətəbl/;
company /ˈkʌmpəni/;
cover /ˈkʌvə/ (UK), /ˈkʌvər/ (US);
done /dʌn/;
dove (a bird) /dʌv/;
dozen /ˈdʌzən/;
front /frʌnt/;
glove /ɡlʌv/;
govern /ˈɡʌvən/;
honey /ˈhʌni/;
London /lʌndən/;
love /lʌv/;
Monday /ˈmʌndeɪ/;
money /ˈmʌni/;
monk /mʌŋk/;
monkey /ˈmʌŋki/;
month /mʌnθ/;
mother /ˈmʌðə/ (UK), //ˈmʌðər/ (US);
none /nʌn/;
nothing /ˈnʌθɪŋ/;
onion /ˈʌnjən/;
other /ˈʌðə/ (UK), /ˈʌðər/;
oven /ˈʌvən/;
shove (to push forcefully) /ʃʌv/;
some /sʌm/;
son /sʌn/;
stomach /ˈstʌmək/;
ton /tʌn/;
tongue /tʌŋ/;
won /wʌn/;
wonder /ˈwʌndə/ (UK), /ˈwʌndər/ (US);
Tip: See my guide to the 
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