He paid the boy $10 for washing ten windows,most of ____ hadn't been cleaned for at least a year.

Thank you for your help,_____ we could not have finished the work in time.

Thelandladywasverystrict.Sheaskedthatwe____televisiononweeknights.

Thetimehascome_____wemakeextensiveuseofnuclearenergy.

Your sister _______to visit you quite ofen,didn't she?