Question

It suddenly occurred to him _____ he had left his keys in the office.

A．whether

B．where

C．which

D．that

Answer 1

D

试题分析：考查固定结构。固定结构it occur to sb that…某人突然想去某事；it是形式主语，真正的主语是that引导的主语从句。That没有任何意思只是在句中起引导作用。句意：他突然想起他把钥匙忘记在办公室里了。故D正确。
点评：。固定结构it occur to sb that…某人突然想去某事；it是形式主语，真正的主语是that引导的主语从句。That没有任何意思只是在句中起引导作用。