求助一篇关于英文邀请信内容为：Write a letter according to the following situation:the Wenchuan earthquake has made this winter extremely difficult for the victims.Write to tell your friend Smith that you are raising money to buy 200 pieces of cotton-padded clothing and some other necessities for the earthquake victims.Ask him to join the charity and show your appreciations for his help.Don’t forget to tell him your phone number 555-5555 for further discussion.Please sign your name as Li Ping.(150-200 words)