单项选择题
My children are looking forward to （） a trip to Beijing next month.
A.make B.making C.be making D.have made
单项选择题 Doyouhaveanyideawhyhe（）？
单项选择题 JustasIwasleavingthehouse，itoccurred（）methatIhadforgottenmykeys.
单项选择题 Aprofessor，alongwithsomestudents，（）nowworkinginthenewlaboratory.
