His success on science____working hard.
--- Sorry, Frank. I’m busy today. I can’t go swimming with you. --- ______ .
--- I can hardly believe such a little boy gets up ______ 5:00 ______ 6:00 every morning.--- What a hard-working boy!
--- I’d like to buy a new house in the center of the city for rent at this special moment.--- Oh. I never doubt ______ it is worth ______ to buy new houses.
--- We need a new leader for our Helping Hands Club, but I don’t know ______. --- Why not Mary? She is always willing to help others.
--- Be quick, ______ we’ll be late for the class.--- Ok, I’m coming.