求一份英语作文(写信的)要用到以下句子的
1;Iamlookingforwardtohearingfromyousoon
2:Yourssincerely
3:wearewritingtointroducethat
4:thankyouforthetroubleyouwillhavetotakefor
5:wehavegreatpleasureinintroducingtoyoubythistroubleyouwillhavetotakefor…….