We should try our best to make ______ world that is safer, cleaner and healthier than ____ one we are living in now.
Lucy ______ at home and read ______ interesting book.
—________do you go to the dentist? —Let me see, twice a year, maybe.
My parents are always worried about what will happen if I .
At school, we are taughtknowledgehow to behave well.
—Listen! Theresomeoneat the door. —It must be your sister.