Theyusuallyhaveaparty______theevening______October1st.A.in,inB.on,inC.on

They usually have a party ______the evening ______ October 1st.A.in, inB.on, inC.on, ofD.on, on

C解析考查介词。在具体的某一天用介词on，根据短语on the evening of…..,故选C。

哦，回答的不错