Connotations – Is the Phrase “Beyond Your Comprehension” Offensive?

I found an answer in this article: 「私は日本人です」は、I am a Japanese. それとも"I am Japanese?

In English there is a distinction between nationalities that end in 'ian' like Canadian or Italian and those that end in 'ese' like Japanese or Burmese.

Those that have the 'ian' can say 'I am Canadian' or 'I am a Canadian' interchangeably, but usually in English the 'ese' ones don't use the 'a' when they're referring to people--unless it is being used as an adjective.

You could say "That is a Japanese person" (where Japanese is an adjective describing the word 'person')

This convention also applies to nationalities that end in 'ish' as well, as in 'I am British' or 'I am Scottish' --though Scotland is a different case because they could say, "I am Scottish" or "I am a Scot".

I don't really know why this convention exists, but saying 'I am a Chinese' to a native speaker would be very strange for them.

Negro is currently considered somewhat offensive in the United States, and it's not advisable to use it if you are first learning the language.

I say "somewhat" because there are circumstances where it is still used, but those circumstances are historically and socially complex, and even Americans still struggle with those circumstances.

It's best to either look for a more neutral term - black or African-American are currently* better choices - or to avoid the reference to race except where necessary. It's also a good idea to take the cue from the person you are describing - what word, if any, would they be comfortable with you using?

*Note: racial relations and language in the US continue to evolve, and what is proper today might be offensive tomorrow.