来自苏炜的问题
.Thepriceofpetrolhasbeen______20percentsincethebeginningofthisyear.A.increasedtoB.risenbyC.increasedbyD.risento
.Thepriceofpetrolhasbeen______20percentsincethebeginningofthisyear.
A.increasedtoB.risenbyC.increasedbyD.risento

