I'd just like to add to some of the terms you mentioned in your awesome article! I think you made a mix up when you said that most Chinese loanwords were of 1 syllable and Mon-Khmer loanwords were of 2 syllables. It is the other way around
Also, it is not ideal to use Mandarin as a comparison for the Chinese loanwords as it has had massive sound changes (as you yourself noticed!) A more ideal comparison would be to Cantonese. For example, 大學/大学 as you mentioned is đại-học in Vietnamese, 대학 dae-hak in Korean, 大学 dai-gaku in Japanese and 大學 dai-hok in Cantonese. Mandarin has merged many sounds and lost the -p, -k, -t endings.
Yes there are plenty of terms with one Chinese syllable and 1 native or other loanword one. Bao tay, bánh bao, cao máu etc…
A car in Vietnamese depending on region is either (xe) ô-tô or xe (hơi). Machinery in general have 2 terms; máy móc (native) or the loaned cơ khí from Chinese. An airplane is either máy bay or phi cơ. A camera is either máy (chụp) ảnh or máy chụp hình.
]]>Yes, Vietnamese borrows some French words such as ca-vát/cà-vạt (a tie), cà-phê (coffee), cao-su (rubber), xà-phòng/xà-bông (soap) etc… but the amount of Chinese loanwords is enormous and as you said equates to at least 50-60% of the Vietnamese words, not counting those older borrowings that were nativised such as năm/niên (year), mùi/vị (flavour), sắt/thiết (iron) etc.
]]>And about hạnh phúc – it is 幸福 in Chinese.
By the way, which atlas did you use for your picture? It looks like it's from the DK Atlas or one of its derivatives.
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