Its my first time seeing 소녀 for girl, too
This is a new word for girl. How is it different?
Different from what? Girl can be 소녀 or 여자아이
What is the difference between 'swi oun' and 'swi gi'
쉬운 is the modifier form (used to describe nouns) of 쉽다 'to be easy'.
쉬기 is the nominal form (noun form of a verb) of 쉬다 'to rest'.
why no 봐요 ?
In my knowledge 봐요 means to look or see and 읽어요 means to read. In this sentence the girl is reading the book, not just looking at it.