英语改错请找出下列句子中的错误,并改正.
1.Ihaveboughtthepianoforsixyears.
2.wherehaveyougone----I’vegonetoshool.
3.Howmanypageshaveyoureadbytheendoflastyear
4.whileIwalkedinthesteet,Isawmyteacher.
5.Theyhavehadtheirlunchattweleve
6.Theworkershaverepairedthemachinesjustnow.
7.Youhavewaitedheresincetwohours