In Chinese, we can say 最真的. 更完美.
However, it is wrong to say "the truest," "the realest" or "more perfect."
Are there any other adjectives not used in the above situations?
So, the general rule is that one-syllable adjectives can take the -est ending.
But you're right, the words "true" and "real" cannot. The reason is that they already represent the "highest level" of an idea.
Something is either true or false. How can it be "more true"?
Something is either real or unreal. How can it be "more real"?
Something is either perfect or imperfect. How can it be "more perfect"?
Native speakers will say these things all the time even though it's not grammatically correct, just for emphasis.
Maybe mandarin speakers believe there are several degrees of perfectness; just like in math there are different degrees of infinity with one greater than others.
On the other hand, if we choose to see perfectness as the highest conceptual limit to something, than maybe in that view it doesn’t make a lot of sense to say “more perfect” or “the most perfect.”
P.S.: However if I remember it correctly, I think I’ve heard the expression “more than perfect” before… Maybe I heard it wrong...
Thank you for your illustration.
Thank you for paying attention to my question.
I would like to know adjectives in English.
Is your question only about Chinese or also about other languages?