It is time 后的定语从句用虚拟语气(在线收听

   从句谓语通常用过去式表示现在或将来,有时也用过去进行时或“should+动词原形”(较少见,且should不能省略),其意为“(早)该干某事了”。如:

  I think it's time you went to bed. 我想你该睡觉了。
  It's time we went [were going, should go]. 我们该走了。
  I think it's time they were taught a lesson. 我想现在该给他们一点教训了。
  注:time前有时有about和high修饰:
  I think it's high time that she made up her mind. 我想她该拿定主意了。
  与其他的虚拟结构不同,该结构不能在该用 was 时而用 were。如:
  It's time I was in bed. 我该上床睡了。(不用were)
  原文地址:http://www.tingroom.com/listen/vocabulary/385769.html