Peter earns ____ his brother does.

— Look, where are you going?— I can’t ________ the map and drive at the same time, can I?

It is necessary for children to exchange ideas with parents from time to time so that the generation gap between parents and children can be _________.

I’ve had a hard life, but it is nothing compared with the hardships that my father ________.

Research shows that humans ______ from selfish to unselfish behavior when they are watched.