I’m not sure whether he has the key that ______ the door of the classroom.
Believe it or not, Levy’s sister suddenly ___________crying when we ere eating.
To our___________, Jane’s illness proved not to be as serious as expected before.
A new situation is likely to ___________when the school leaving age is raised to 16.
Last summer I took a course on___________poisonous gases.
She had to ___________four young children after her husband died.