单项选择题
Washington, the capital of the US, is on the （）river.
A.Potomac B.Delaware C.St. Laurence
单项选择题 （）has the sole right to interpret the Constitution.
单项选择题 The First Continental Congress was held in （）in September, 1774.
单项选择题 Among the five Great Lakes, only （）is wholly within the United States.
