They arrived here . A.since a week ago B.a week ago C.for a week D.next weekThey arrived here . A.since a week ago B.a week ago C.for a week D.next weekThey arrived here . A.since a week ago B.a week ago C.for a week D.next week呵呵...请给出为什么选这个答案的理由.

问题描述:

They arrived here . A.since a week ago B.a week ago C.for a week D.next week
They arrived here .
A.since a week ago B.a week ago
C.for a week D.next week
They arrived here .
A.since a week ago B.a week ago
C.for a week D.next week
呵呵...请给出为什么选这个答案的理由.

B.a week ago
They arrived here 时态是一般过去式,所以用过去的时间状语
ago通常做时间状语用一般过去
A.since a week ago 完成时
C.for a week 完成时
D.next week 将来时
这是选B