Solidgeometryhasenabledastronomerstocalculatethepositionsoftheheavenlybodiesrelativetooneanother.
A、ontopofTheflowerbudofawaterlily百合opensatsunsetsince.itsopeningistriggered(commence).bythedecreasedlight.
MaryMcCarthyssatires讽刺文学arecouchedinaprosestylethathasaclassicprecision.
TheSalkvaccineisamajorfactorinthefighttoeradicatepolio.
Oneofthegreatestbreakthroughsforprofessionalwomencamein1973whenthefieldofbankingopenedupforthem.
ThefirstimportantexpositionintheUnitedStateswasheldinPhiladelphiain1876.
