My sister is very lazy. She _________ helps my parents with housework.

Who helped you clean the window, Jack-_______________. I cleaned it by myself.

A problem has occurred we should develop innovative thinking abilities in the classrooms by giving students opportunities to generate new ideas.

How long do you think it will be _____ President Hu Jintao makes another visit to America?—It all depends[ ]

Under good treatment, she is beginning to ______ and soon come back to work.