The program was so exciting that the children kept their eyes _____ on the screen.
Nancy enjoyed herself so much __________ she visited her friends in Sydney last year.
Peter was so excited __________ he received an invitation from his friend to visit Chongqing.
You can't borrow books from the school library __________ you get your student card.
She had just finished her homework __________ her mother asked her to practise playing the piano yesterday.
The girl had hardly rung the bell __________ the door was opened suddenly, and her friend rushed out to greet her.