1．The final exam is coming and all the students are ________ their study.
2．The parents decided to employ a private teacher ________ help her with maths.
3．It's necessary for you to ________ your mother ________ your arrival early.
4．The professor felt easy because his two students would ________ him ________ the experiment.
5．It's natural that children ________ their parents for food and clothes.
