They have got lost, or had an accident.
Charlie ______ be really difficult at times even though he’s a nice person in general.
It was only after I came across that matter_______ how important it was to master a foreign language.
--- When shall we meet again, Tom? --- Make ______ day you like; it’s all the same to me.
As a result of the serious earthquake, two-thirds of the buildings in that area _______.
Every athlete as well as some coaches who ____ to go to the Games ____ asked to be here before 7:30 am.