She _____ have left school, for her bike is still here.[ ]

o cause people some health problems, in fact farmore serious _____ than computers do

feel sure that ______ qualification, abilityand experience, you are abundantly suited to the position we have in mind.

The mother just now learnt that her son hadn’t stolen the money. She regretted ___ him yesterday.

Tom and John are going swimming with________ boys this afternoon