beautiful

BEAUTIFUL (adjective)
1. (of person) having an attractive quality that gives pleasure to those who experience it or think about it
beautiful girl
2. (of thing) pleasant to look at
beautiful dress
3. pleasant
beautiful weather, beautiful song, beautiful music
4. done or made very well or with lot of skill
The second goal is beautiful

PRETTY (adjective)
1.(of person) pleasant to look at, or (esp. of girls or women or things connected with them) attractive or charming in a delicate way
pretty girl, pretty face
2. (of thing, building, place) attractive, in a delicate way, but not really beautiful or impressive
pretty dress, pretty village

分別:
A pretty girl or woman is good-looking in a fairly ordinary way and has a nice face.
Beautiful is a stronger word, used to describe someone who is unusually attractive and has perfect good looks

其他分別:
Pretty 並且可作 adverb, beautiful 只能作 adjective

PRETTY (adverb) – very, fairly
He looks pretty tired.

pretty(adv),fairly;It's pretty hard to explain.
---(adj)attractive without being very beautiful;
----eg:- a pretty little girl; a pretty face,
----eg:- look so pretty in that dress only.

Beautiful(adj):-having beauty; pleasing to the senses or to the mind or heart;
---eg:- a beautiful woman;
---very good or skilful:-eg:- What beautiful timing on figure-skating!