Question

---There’s someone knocking on the door. Who _________ it be?---It must be John. He promised to..

---There’s someone knocking on the door. Who _________ it be?---It must be John. He promised to be here at 8:00. A．must B．can C．need D．shall

Answer 1

B

试题分析:考查情态动词用法。A必须；B能够，可能；C 需要；D将会。从句意可知此处表示推测，而must表推测时只用于肯定句，C、D选项意思不恰当，can表推测可以用于否定句和疑问句表示“可能”，所以B选项正确。句意：--有人在敲门。可能会是谁呢？--肯定是约翰。他答应八点钟来这儿了。