With lasers scientists can probe many physical processes, such as combustion, once beyond our ken.视野
A、understandingA
暂无解析
Themegaphone(microphone)makesthevoicesoundlouderbecauseitpointssoundwavesinonedirectionandkeepsthemfromspreadingoutinalldirections.
Creamoftartar酒石,aweakacid,canbeaddedtoeggwhitestohelpthemfoam泡沫whentheyarebeaten
DoubleEagleinthefirsttransatlanticballoon,wasgreetedbyavidcrowdsinFrance.
Despitetheproliferationofotherfastermodesoftransportation,therailroadsremainthelargestcarriersofintercityfreightintheUnitedStates.
Peoplewhodonotsleepenoughtendtobecomeirritable.
