Please don't use the word "phrase" easily upstairs. Usually, it is almost the same to say the word combination. If you have to say that there are phrases in Chinese, it is an idiom!

"No" stands for adverb and "Yao" stands for verb! The reason is that verbs are words that express actions or states, while words that modify verbs and adjectives in Chinese are adverbs, but they cannot change the part of speech of verbs or adjectives, such as too and very.