单选题Why haven't you finished&

问题补充：

单选题Whyhaven youfinishedyourhomeworkyet?You___________tohavefinisheditbylastSunday.A.are supposedB.were supposedC.are supposingD.were supposing

答案：

B解析本题考查的是be supposed to的用法。题意为“你为什么还没完成作业?你上个周日就应该完成了。”在本题中be supposed to have finished相当于should have finished，意为“本来应该完成而实际上没有”。