Question

【题目】Robert was very upset that most of his friends ______ when he ______ at the party.
A.had left; arrived
B.left; arrived
C.left; had arrived

Answer 1

【答案】A
【解析】句意：Robert很不安，因为当他到达聚会的时候他的大部分朋友已经走了。根据句意，他到达是过去的时间，用一般过去时，朋友们离开是在他到达之前发生的，也就是过去的过去，因此用过去完成时，故选A。