people mercurial mood I was feeling very upset yesterday night,then my friend told me everyone will have a period of sadness after a time,so i went to sleep ,it was so amazing,when i got up this morning,i'm happy again,just like nothing happend yesterday night.but i really feld very sad at that time...

what means XD? thank you for help me

how to improve my English speaking skill ?help~ i have no problem in writing english,but when i have a voice chat with my foreign friends ,i will absolutely don't know how to express my mean~

sure 和 of course有什么不同呢。Is there anything different between "sure"an"of course"? when people was asked to do sth,and they are willing to do it .

My favorait singer Declan Gailbraith He is really a great singer ,he showed his talent when he was only 8 years old ,the song <tell me why>had shakened me,and when i heard <an angel> i was really on fascinated.his voice was so wonderful.There are many fans of him in China,they call themself as "December",and they all crazy on him.Declan was born in the december of 1991,the same year and month with me.Although his voice has changed,not as sweet as initial,but still attractive.He had a China-concert in2008,and his news are infrequent recently.i hope he can take more beautiful songs to us.