Question

Was it 8 o’clock ________ you heard someone ________ at the door?

[　　]

A．

when; knocking

B．

when; knock

C．

that; knocking

D．

that; knock

Answer 1

答案：A
解析：

句意為：你聽到有人敲門時(shí)，是八點(diǎn)鐘嗎？it指時(shí)間，when引導(dǎo)的是時(shí)間狀語從句。容易將此題誤認(rèn)為是強(qiáng)調(diào)句�？稍�8 o’clock前加at以驗(yàn)證，排除C、D兩項(xiàng)，即when引導(dǎo)定語從句；有具體時(shí)間，所以應(yīng)該是“聽到某人(在此時(shí))正在做某事”，感官動(dòng)詞后加賓語和現(xiàn)在分詞作賓補(bǔ)。