[译] 傍晚她要去参加一个化装舞会。
[误] She would be going to a make-up party in the evening.

[正] She would be going to a fancy dress party in the evening.
[注] make( dress) up 意为"化妆"，指妇女打扮自己，或演员化装，如: It is most unseemly for women to make up in public. 妇女当众化妆不甚雅观。/The actress made herself up for the part of a young girl. 那位女演员化装成一个年轻的姑娘。"化装舞会"指穿着奇装异服，带面具的舞会。可以说: fancy dress party, fancy dress ball, fancy ball 等。