Question

Mr White ________ at 8∶30 for the meeting, but he didn't show up．

1. A.
   should have arrived
2. B.
   should arrive
3. C.
   should have had arrived
4. D.
   should be arriving

Answer 1

A
全句意為“懷特先生8∶30(原本)應(yīng)該到會(huì)的，但他沒(méi)露面”。全句談的是過(guò)去應(yīng)做的事但沒(méi)有做，故應(yīng)使用should have done結(jié)構(gòu)，表原本該做而沒(méi)做某事。故答案為A。
一定要掌握should have done/ought to have done表示“應(yīng)該做的事而未做”。同時(shí)，也要注意情態(tài)動(dòng)詞的同類(lèi)結(jié)構(gòu)的不同用法。如：must have done表示對(duì)過(guò)去肯定的推測(cè)，can't have done是表示“對(duì)過(guò)去否定的推測(cè)”。