I haven' t seen Mary these past few days. I m afraid she ____ herself for some time.
—I wonder if I could use your phone?— ________.
Do you have any idea ________ is actually going on in the classroom?
— Can you give me some advice on what I said just now?—Sorry. My mind ________.
Chemicals in the body ______our food _____ into useful things.
—Peter looked tired and a little absent-minded in class. —He _____ too late.