ThefirstimportantexpositionintheUnitedStateswasheldinPhiladelphiain1876.
更新时间:2024-11-24 01:00:37 A、exhibitionThe wheels of the first road vehicles were fashioned from crude stone disks.
Formulatedin1823,theMonroeDoctrineassertedthattheAmericaswerenolongeropentoEuropeancolonization.
When carbon is added to iron in the proper proportions , the result is steel.
Some cosmetics manufacturers attempt to capture the rose's unmistakable fragrance香味 in soaps and perfumes.
Cream of tartar 酒石 , a weak acid, can be added to egg whites to help them foam泡沫 when they are beaten
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