单项选择题
During the Civil War, Steam Boating on the lower Mississippi River was（）．
A.ruinedB.delayedC.destroyingD.damaging
单项选择题 There is an interesting old（）on top of the hill．
单项选择题 I was（）by that law case，I'm a（）man．
单项选择题 He had never spent a（）day.
