天山新题20 18

christinahong

18.Interest rates on mortgages （have declined steadily during the first six months of this year but virtually remained unchanged ）during the next three months.
(A) have declined steadily during the first six months of this year but virtually remained unchanged
(B) declined steadily during the first six months of this year but virtually remain unchanged
(C) steadily declined during the first six months of this year but remain virtually unchanged
(D) declined steadily during the first six months of this but have remained virtually unchanging’
(E) declined steadily during the first six months of this year but have remained virtually unchanged
答案：E
时间状语during the next three months可以决定用现在完成时have remained ？during the next three months在一般的情况下应该用将来时吧？
B中的remain 可以吗？

bluestone1

since 一般用 完成时

during 何解呀？ 有时完成 ， 有时过去

请高人指点一二

linlin315

我认为：现在完成时表示的是某一个动作持续到现在并且还有可能继续持续下去。
during the first six months of this year 很明显是表示过去的一段时间，declined 这个动作也已经完成了，所以不可能用完成事态的，所以应该用过去时
during the next three months可以用完成时态，来表示动作持续下去的趋势...

bluestone1

thanks, 很清楚了