The poor child stood there, and ________ what to do, turned to his father for help.[ ]

Jay Chou plays the role Kato the film The Green Horney.

Hurry up! The bus is coming.– Wait a minute. Don’t cross the street ____ the traffic lights are green.

The factory ______ last year was equipped with the latest machinery

_______ no one agreed with him, ______ he insisted on learning play the piano.