it really sucks >> it really sucked (past tense needed)
is American accent >> was an American accent
the girl speaked fucking quickly >> the girl spoke fucking quickly
my 21th birthday >> my 21st birthday
become older >> I became older
the classmates >> my classmates
showed me the fireworks >> showed me (some) fireworks
i did make my wishes >> I made many wishes
hope they all can come true >> I hope they all will come true

mostly tense problems.. either you choose present tense or past tense, you can't use both. for this paragraph, past tense seems more suited. present tense sounds awkward. 

My first lesson to you is to learn the capitalization rules of English!  If you don't know see

http://www.italki.com/knowledge/page/On%20Capitalization.htm

If you don't understand, ask. :)

birthday and damn cet6

yesterday was a busy day,finished the damn cet6 finally,but it really sucks,,the listening part is American accent,it should be ok for me,but!!!the girl speaked fucking quickly,,- - maybe should try it again next year.
but yesterday was important for me,,my 21th birthday,,ahh,,,become older ,^^
anyway ,i was soooo happy ,i got lots of gifts and 4 birthday cakes ,flowers and cards from all the classmates ,my buddy showed me the fireworks,it was amazing, i did make many wishes ,hope they all can come true.