The adoption of orphans and physically challenged children has been a subject of public debate _______ a fire in an unregistered orphanage last month.

At the railway station, the mother waved goodbye to her daughter until the train was _______.

—Why do you eat so little?—I’m _______ a diet to reduce some weight.

At proper horse races everyone has already studied the form of the horse ______.

Margaret liked all her classes, but she liked sewing class _____.