Themegaphone(microphone)makesthevoicesoundlouderbecauseitpointssoundwavesinonedirectionandkeepsthemfromspreadingoutinalldirections.
A、slitheringSomeanimalspantandsweattospeedevaporationofbodymoistureandthuscoolthemselves.
Despitetheproliferationofotherfastermodesoftransportation,therailroadsremainthelargestcarriersofintercityfreightintheUnitedStates.
Cream of tartar 酒石 , a weak acid, can be added to egg whites to help them foam泡沫 when they are beaten
Alllivingorganisms,regardlessoftheiruniqueidentity,havecertainbiological,chemical,andphysicalcharacteristicsincommon.
Some cosmetics manufacturers attempt to capture the rose's unmistakable fragrance香味 in soaps and perfumes.
