In 1942, Columbus and his crew arrived ________ was so-called the New World by the westerners.
Is this museum ___ some foreign friends visited that day?
Edison never stopped ___ new and better ways to do things.
Although it’s raining, ___ are still working in the fields.
Is ___ possible to fly to the moon in a spaceship?
Of all the boys, Tom spent __ time and made ___ mistakes.