问几个高中英语单选
1.The research is so designed that once _____nothing can be done to change it.A.begins B.having begun C.beginning D.begun
2.I would appreciate_____back this afternoon.
A.you to call B.you call C.your calling D.you're calling
3.The managers discussed the plan that they woukd like too see____the next year.
A.carry out B.carring out C.carried out D.to carry out
4.The mayor of Beijing says that all construction work for the Beijing Olympics_____by 2006.
A.has been completed B.has completed C.will have been completed D.will have completed.
主要是讲解 书上没具体解释
鄙视下 新申请的号 分不多