问题补充:
单选题______,thesubjectwasalwaysinmymind.A.Walking or sleepingB.Walking or sleptC.Having walked or sleptD.To walk and sleep
答案:
A解析题意为“无论是走路还是睡觉,我总是在想这个问题。”注意:此题中-ing形式短语的逻辑主语与句子的主语并不一致,有的语法家称其为“垂悬分词”。又如:Having suffered such heavy pollution already, it may now be too late to clean up the river.