The policeman kept his eyes________on the screen of the computer to identify the criminal's footprints.

The housing problems we are looking forward to seeing _____ have attracted the government’s attention.

He was seen ______ a letter in his bed room.

_______ from view day by day, the singer isi turning to his memories for comfort.

Studies show that MP3 people have made much use of _____ music may be causing hearing loss.