Themegaphone(microphone)makesthevoicesoundlouderbecauseitpointssoundwavesinonedirectionandkeepsthemfromspreadingoutinalldirections.
A、slitheringDoubleEagleinthefirsttransatlanticballoon,wasgreetedbyavidcrowdsinFrance.
Oneofthegreatestbreakthroughsforprofessionalwomencamein1973whenthefieldofbankingopenedupforthem.
Urbanrenewalprogramsstrivetoupgradeareasthatarebecomingslums.
Alligatorsstillexistinsomeofthedank潮湿swampsandbayous小海湾ofAlabama'scoastalregions.
ThefirstimportantexpositionintheUnitedStateswasheldinPhiladelphiain1876.
