Hello, This is a difficult question to answer. The words "degree" and "level" have very similar (nearly identical) meanings. They are (more or less) interchangeable. In my opinion, "level" is a more rigidly defined word (levels are more strictly defined) whereas "degree" acknowledges the small differences between levels and more variable term. You can have many varying degrees of something, as opposed to a set number of levels. Sorry if this is confusing- just remember that the two words are synonyms. Hope this helps!

"I am Chinese" is a grammatically correct sentence simply using the adjective "Chinese" to describe yourself. "I am a Chinese" is grammatically incorrect. You could say, "I am a Chinese person" or "I am a Chinese citizen." The reason why you need a noun such as person or citizen in this case is because you used the article "a" before "Chinese." This implies that there will be a noun used in the sentence and there is not. You must insert a noun (such as person, woman, citizen, etc) or eliminate "a" from your sentence. Hops this helps!