Talk about Nationality - I am a Vietnamese?

[Squirrel_3110]

I'd like to ask you about how to talk about nationality. Should we use a/an before nationality?
For example: I am a Vietnamese and I am Vietnamese, which one is correct?Why? Thank you very much!

[solnadya]

when you say 'I am Vietnamese, it means 'my nationality is Vietnamese.

when you say 'I am a Vietnamese', it means 'I am a Vietnamese man/ woman / person'.

The idea is almost the same, you just express it differently, so the grammar rules for 2 ways are different

[thod00]

In saying "I am Vietnamese", 'Vietnamese' is used as an adjective to describe yourself, much like saying "I am tall".

With "I am a Vietnamese", 'Vietnamese" is a noun, "I am a man".

It just happens that with Vietnam these are the same. But consider Sweden, "I am Swedish" -> "I am a Swede" or "I am Spanish" -> "I am a Spaniard".