Some of you may have finished unit one._____; you can go on to unit two
A.If you mayB.If you doC.If notD.If so在线课程D
解析：
考查省略。If so ="If" you have done so。句意：你们中的一些人可能已经完成第一单元,如果这样的话,你可以继续第二单元。