1.Allflightsbecauseofthestorm,theydecidedtotakethetrain.A.havingbeencancelledB.havebeencancelled为什么选A?不能选B?2.thattherearenoobjection,wewillbeginwithitemthreeontheagenda.A.IfB.Provided为什么选B,

Question

1.All flights_____because of the storm,they decided to take the train.
A.having been cancelled B.have been cancelled
为什么选A?不能选B?
2._____that there are no objection,we will begin with item three on the agenda.
A.If B.Provided
为什么选B,不能选A?
3._______is the center of our planetary system was a difficult concept to grasp in the Middle Ages.
A.That the sun and not the earth B.It is the sun and not the earth
为什么选A?不能选B?
4.I______to go to their party but I was not invited.
A.should have liked B.would like
第4题为什么选A？不能选B？

Answer 1

1.,号不能连接俩个句子,所以第一个句子要用独立主格,也就是说要非谓语.
2.虚拟语气省略if
3.主语从句,that无实际意义,选B有俩个is,句子残缺.
4.should have done 本可以却未...意思是我本可以参加她们的聚会,但是我没有被邀请.B的意思是我愿意,不是所考知识点.