The United States is（).A、a formerB、ritish colonyB、an economic powerC、a cruel oppressorD、

Press Association is a national news agency ofA．the United Kingdom.B．the United States.C．C

In the United States, the Senate is presided over by______of the United States.A．the presi

______forms a natural boundary between Mexico and the United States.A．The Rio Grande River

共用题干The United States is a federal union of 50 st

共用题干The United States is a federal union of 50 st

A．The United States is huge.B．Public transportati