omission of the consonant at the end of words ending in a diphthong and a consonsant, for instance "Mickey Mouse" pronounced "Mickey Mao", "white wine" pronounced "why why", and "news" pronounced "new".
inability to speak consecutive consonants, for instance "slow" pronounced "sah-low"
using "N" to replace an "L" sound at the end of the word, for instance "school" pronounced "skoon" or "football" pronounced "futbon"
moving "S" on singular verbs to the subject, for instance "He's talk too much" instead of "He talks too much"
omission of prepositions, for instance "I wait you" instead of "I'll wait for you" or "I listen him" for "I listened to him".
confusion between using "very" (which should be used before adjectives, past participles used as adjectives, and adverbs) and "very much" (used after verbs), for instance "I very love my daughter" and "She beautiful very much".
The words of Thai prefix particles and their implied meanings:
Khun (Thai for Mr, Mrs or Miss) instead of Mr or Ms (e.g., Khun Somchai will have a meeting on Friday.)
Following is the list of Thai final particles and their implied meanings:
la = to give suggestion (e.g., Why don't you ask her, la?), to inform the listener of something (e.g., I'm going to bed, la.), or to ask if the subject would do something that the subject of the previous sentence does (e.g., I'm going to have dinner now, how about you, la?)
na = to give a suggestion (e.g., You must do your homework first, na.), to inform the listener of something (e.g., I'll be right back, na.), or to soften a statement about something that the speaker thinks should have been done but have not yet been done (e.g., Why don't you ask her, na?)
cha/ja = to add informality to the conversation (e.g., Hello, ja.)
khrap/krab (or, alternatively, krub) (for male speaker only) = add at end of sentence to make the conversation polite/formal; also as confirmation (Yes!) (e.g., Hello krab.)
kha (or ka) (for female speaker only) = same as krab (e.g., Hello kha.)
Some less common particles:
mang = a qualifier indicating uncertainty, sometimes translated as "maybe" (e.g., The shop already closed, mang. / I think he's 25 years old, mang.)
loei = totally or immediately (e.g., I don't understand loei la. / See you there loei na)
laeo = already or done (e.g., I have to go laeo la.)
na = to give suggestion (it's likely to be used with someone who's close to you and of equal status, such as your close friend) (e.g., I don't know at all, na, why don't you come with me, na?)
wa (วะ) = Adds emphasis (e.g., Going to watch a movie, wa!). Impolite. Only used with friends or when very angry.
As some sounds in English just simply don't exist in Thai language, this affects the way native Thai speakers pronounce English words:
Non-rhotic, e.g., more -> maw ([mɔː]), gear -> gia ([kia]), and car -> kah ([kʰaː]).
all syllables are stressed with the same intensity
omits consonant clusters. "Mixed" is pronounced "mik".
final consonants are often omitted or converted according to the rules of Thai pronunciation: l and r become n; p; b and f become an occlusive p; t, th, d, s, st, sh, ch and j become an occlusive t.
Perversely, given the language constraints for d and l among the rules above, l can become r and d can become sh, for instance blood can become brush.
If there is more than one consonant at the end of a syllable, only the first is pronounced, the others are omitted. "W" and "Y" sounds count as consonants, too. So, "count down" becomes "cow dow", "size" becomes "sigh"
"sh" and "ch" sounds can be indistinguishable as the Thai language does not have the "sh" sound, e.g., ship/chip, sheep/cheap
"v" sound is almost always replaced by "w" sound, e.g., vow -> wow, ville -> will
"g" and "z" sounds are usually devoiced, e.g., dog -> dock ([ˈdɔk]), zoo -> sue ([ˈsuː])
"th" sound is often replaced by "t" or "d" sound. Particularly, the voiceless "th" (/θ/) is replaced by [t] or [tʰ], while the voiced "th" (/ð/) is replaced by [d], e.g. thin -> tin ([ˈtin]) or [ˈtʰin]), through -> true ([ˈtʰɹuː]), thank you -> tang kyou ([tɛŋ kiw]) or ([tʰɛŋ kiw]), and then -> den ([ˈden]).
ambiguity between the short "e" (/ɛ/), as in "bled", and a long "a" (/eɪ/), as in "blade" because both are pronounced as [e(ː)].
"e (vowel) " such as cherry is pronounced shire-ry, error is pronounced err-rer
In Thai, certain consonants cannot occur as a consonant cluster. Such illicit clusters include those with sibilant sounds followed by obstruent sounds. In order to avoid such illicit forms, a short "a" (ah; [ə]) sound is added between these consonants:
start - sahtat (/səˈtaːt/)
sleep - sahleep (/səˈliːp/)
speak - sahpeak (/səˈpiːk/)
snore - sahnore (/səˈnɔː/)
swim - sahwim (/səˈwim/)
school - sahkoon (/səˈkʰuːn/)
album - alabum (/ələˈbam/)
'R' or 'l' after another consonant may be omitted completely.
^Kong Rithdee (2012-03-10). "Davos, Tokyo and clueless Tinglish". Bangkok Post. p. 7. Seriously, watching that clip, I rooted for her to pull it off, to show that Suvarnabhumi English, our Tinglish, is as good as any as long as what she meant to say came off.