—Who’s that boy reading in the study ? Is it David?—It __________ be David. I saw him go home just now.
There _____ lots of traffic on the road, so I didn’t catch my plane on time.
Millie has a few roses in her hands,___________?
Li Ming speaks English very well, but of course not _____ the people born in England.
---When did they _______Shanghai? ---They ______there at 2:00 p.m.
---Is Mrs Wang ready for the party? ---___________.