—Mr. Hu, can you tell us how to learn swimming well?—Sure. But remember we can learn nothing well _______ hard work.
—What do you usually do _____ weekdays after school? —I usually read books.
—_____ does Kangkang meet his friends? —Four times a month.
The boy likes playing _____ basketball very much.
Bob often _____ his homework after dinner.
The Browns usually drive to the park on Sundays. But today they go to the park_____ foot.