发布时间: 2016年03月31日
词汇选项
To understand what we are going to talk about today,you have to rely on what you have read previously.
A.beforehand
B.carefully
C.before
D.in advance
正确答案:C
答案解析:previously 是副词,“以前。先前”,和作副词用的before同义;beforehand 和 in advance意思相同,都是“事先,预先”的意思。