are some health problems that, when ____in time,can become bigger ones later on.

It was __________ computer games thatcost the young man a lot of precious time that he ought __________ on hislessons

_______ the farmers discovered the entrance to the secret cave in the valley— Totally by chance.

no ________ to the plan, so long asit would not cost too much.

Alice, please tell Eric to call me when he _____ back. –No problem.