問題補(bǔ)充：
單選題
I ________ asleep because it took me a long time to realize that the telephone was ringing.A.could fallB.need have fallenC.must have fallenD.may fall
網(wǎng)友答案：
熱心網(wǎng)友 1樓
C解析考查情態(tài)動(dòng)詞表示推測的用法。must have done 表示對過去事情肯定的推測，句意：我當(dāng)時(shí)一定是睡著了，因?yàn)榛宋液瞄L一段時(shí)間才意識到電話正在響。故選C。
