Mary and her classmates are going a social st

问题描述:

Mary and her classmates are going a social st
Mary and her classmates are going a social studies field trip.这道题填什么呢?

答案:on
go on a...trip进行一次……的旅行.
句意:玛丽和她的同学们将要进行一次社会实验方面的旅行.