24. In the reading room, we found her ______ at a desk, with her attention _______ on a book.
In front of the classroom___
___sign the contract unless you are sure you understand it.
Eyewitness provides an evidence that he was ___ of the crime.
Wash your hands with soap and water ___ after each contact with the sick person.
After the fun he has had during the holidays, the boy can’t ___ on his schoolwork.