Medium build medium build (including bodybuilding, height and weight)
The build here comes from the phrase build oneself/sb up to make you healthy and strong.
usage
I have (a) medium build
I am of medium build
I am a person with (a) medium build
Average height is of medium height
usage
I have (the) average height
I am of average height
I am a person with (the) average height
Is this sentence correct?
Absolutely right! ! But there are two things you should pay attention to:
1. You must say this completely in your oral conversation with others, because many foreigners say this, and quite a few English don't pay much attention to its grammar in spoken English. This usage of yours is often used by people in English-speaking countries.
2.medium build and averge height are generally not used together. Because medium huild has implied the meaning of height. But if you want to emphasize your height, it is not impossible.
Grammatically correct combinations are not enumerated one by one:
I have (the) average height and (a) medium build.
I am of average height and have (a) medium build.
Build and height are both countable and uncountable nouns, and you can add no crown word before them. There are no the and a after of.