______ a little earlier, I would have caught the train.
C
本题考查的是if引导的虚拟条件句，省略了if要把had提前。
Themissingboyswerelastseen________neartheriver.
NeitherEnglishnorChinese________difficulttolearn.
Thegirlwasluckyenoughto_______thebadmenandranaway.
______alittleearlier,Iwouldhavecaughtthetrain.
Heshookhandswiththevisitors________astoconveyhisapology.