My student says they have no dirty washing but they have been here for a week.
You may have offered to do all of your student's washing but they may prefer to do their own. Renegotiate with your student, remembering that female students will not want their underwear on public display. Explain current water restrictions in Australia in a gentle, non-authoritarian manner.
I told my student to 'help themselves' because I was going out but when I arrived home they had not eaten.