. The only Sinitic
language (language of Chinese origin) that is written in a latin
script, designed thanks to the efforts of Portugese missionary Alexandre de Rhodes
The English 'd' sound is written with a crossbar. Without a crossbar it is pronounced as a 'z' in the north and a 'y' in the south. There are a few other characters that are pronounced differently between the north and south, but most do not vary markedly from English (and unlike English, Vietnamese is mercifully free of homonyms
There are no f, j, w, or z characters used (although Viet Kieu
and more modern Vietnamese named Dung may change their name to Dzung)
Like Chinese, it is multi-tonal, with diacritic marks placed above or below a vowel character. Pronouncing phonemes with differing inflections will change the meaning of what you say. In English we change the tone of our voice to convey emotion, so if you become excited or agitated when speaking Vietnamese, be careful how you speak or you may become unintelligble like Donald Duck.
Sentence structure is simple - subject verb object. Passive voice is marked with either duoc (if what happened is a good thing) or 'bi' (if it sucks). Add 'đã' to make it past tense, 'sep' to imply an event is about to happen, se to make it future and 'dang' to make it continuous. Negation is achieved with adding in a 'khong', but if something hasn't yet happened, use 'chua' instead.
There are a complicated arrangements of personal pronouns used, depending on what age, gender, family relationship and status differences exist between the speaker and listener. Amazingly however, Vietnamese speaking English will still manage to mix up 'he' and 'she'. Objects are referred to with different classifiers depending on what they are - bottles, animals, machinery etc.
About half of all words come from Chinese, and the remainder are either indigenous, Khmer or French in origin. There are also vocabulary differences between the north and south. A northerner would say Toi bi om if they are sick; a southerner would say Toi bi dau.
By the way, finding the right code for each diacritic is a bit of a pain, so please excuse the fact I haven't included them.