0a) these don't sound natural. Using 'opening' makes it sound as though your mother officially opened the party with a ceremony - like a mayor opening a new building by cutting a ribbon. You don't make a party.
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01cite10Grammar Geek12cite12br10Yes, we do 01i00throw parties02i00 in the UK too.02br
10In the UK, do you "throw" a party? You use that in the U.S.12br
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