问题补充：
单选题IwonderwhyJenny____usrecently.Weshouldhaveheardfromherbynow.A.hasn’t writtenB.doesn’t writeC.won’t writeD.hadn’t written
答案：
A解析前句中recently与事句中动词民用的语气为重要提示：We should have heard from her by now.=We haven,t heard from her by now此处讨论最近该发生而没发生的事，用现在完成时态：…hasn’t written us recently.
