Can we use لي with rational nouns.
eg. لي كتاب
Or else only with non rational nouns.
eg: لي اخ واحد
Yes of course you can use it.
Other examples
عندي كتاب
في المدرسة معلمون
على الشجرة عصفور
lol i am arabic
The word "لي" is a possessive pronoun in Arabic that translates to "my" in English. It is used to indicate ownership or possession of something.
In Arabic, "لي" is generally used with non-rational nouns, which include both non-living objects and abstract concepts. This includes things like "لي كتاب" (my book) or "لي سيارة" (my car).
However, it is important to note that for rational nouns, which refer to living beings like people or animals, the possessive pronouns "لي" and "لك" are not commonly used. Instead, the noun is usually accompanied by a separate possessive pronoun suffix. For example, to say "my brother" in Arabic, you would say "أخي" (akhi) instead of using "لي" ("لي أخ واحد" is not correct).
So, in summary, "لي" is typically used with non-rational nouns in Arabic to indicate possession, while rational nouns usually require the use of possessive pronoun suffixes.