ne has a responsibility to save _____water, if future generations are to enjoy a similar standard of living to _____we enjoy now

Must I do the rest of the work today?— No, you _________finish ittomorrow.A．must

This I did at nine o’clock, after _______ I sat reading the paper.

periment shows that proper amounts ofexercise, if __ regularly, can improve our health

The children without parents ______ good care of bytheir teachers in this special school.